United States Patent (19) 11 Patent Number: 4,496,778 Myers et al. (45) Date of Patent: Jan. 29, 1985 (54) PROCESS FOR THE HYDROXYLATION OF 56 References Cited OLEFINS USING MOLECULAR OXYGEN, U.S. PATENT DOCUMENTS ANOSMIUM CONTAINING CATALYST, A COPPER CO-CATALYST, AND AN 2,773, 101 12/1956 Smith et al...... 568/860 AROMATIC AMINE BASED PROMOTER 3,317,592 5/1967 Maclean et al. . ... 568/860

3,337,635 8/1967 Norton et al...... 568/860 75 Inventors: Richard S. Myers, Fairlawn; Robert 4,390,739 6/1983 Michaelson et al...... , 568/860 C. Michaelson, Waldwick; Richard FOREIGN PATENT DOCUMENTS G. Austin, Ridgewood, all of N.J. 32522 8/1974 Japan ...... 568/860 73) Assignee: Exxon Research & Engineering Co., Primary Examiner-J. E. Evans Florham Park, N.J. Attorney, Agent, or Firm-Robert A. Maggio 21 Appl. No.: 538,190 57 ABSTRACT A process directed to the hydroxylation of olefins by 22 Filed: Oct. 3, 1983 reacting said olefins in the presence of oxygen, water, and a catalyst composition comprising (i) a catalytically 51 Int. Cl...... C07C 29/04; CO7C 31/18; active osmium containing compound, (ii) a Co-catalyst C07C 31/22; CO7C 31/42 I comprising a copper containing compound such as 52 U.S.C...... 568/860; 260/.397.2; CuBr2, and (iii) a Co-catalyst II capable of increasing 560/186; 562/587; 568/811; 568/821; 568/833; the rate and/or selectivity of the hydroxylation reac 568/838; 568/847 tion, such as pyridine is disclosed. 58 Field of Search ...... 568/860, 833, 811, 821, 568/838, 847; 562/587; 560/186; 260/.397.2 31 Claims, No Drawings 4,496,778 1. 2 that the reaction is highly pH dependent (see Schroder, PROCESS FOR THE HYDROXYLATION OF page 210, Col. 1). OLEFINS USING MOLECULAR OXYGEN, AN The poor performance of oxygen based osmium cata OSMIUM CONTAINING CATALYST, A COPPER lyzed olefin hydroxylation systems is unfortunate, since CO-CATALYST, AND AN AROMATIC AMINE 5 such systems have inherent advantages over organic BASED PROMOTER hydroperoxide based systems. For example, hydroxyl ation systems employing organohydroperoxide oxi BACKGROUND OF THE INVENTION dants result in the conversion of the organohydroperox ide to its corresponding alcohol during the formation of The present invention relates to a process for con 10 the desired olefin derived diol. Thus, for example, t verting olefinically unsaturated compounds directly to butylhydroperoxide is converted to t-butylalcohol. The their corresponding diols or polyols in the presence of a commercial attractiveness of such processes is depen specifically defined oxidation catalyst composition, wa dent on the ability to use or sell the organic alcohol ter, and an oxygen containing gas. co-product in addition to the diol. Given the fluctuation It is well known from the technical literature, that 15 in economic conditions, however, it may be difficult to olefins can be oxidized to their corresponding diols, dispose of large quantities of these organic alcohol co stoichiometrically or catalytically with osmium oxide products in an economically attractive manner. In any compounds, particularly osmium tetroxide. event, it can be troublesome, when the quantity of one The non-catalytic, i.e. stoichiometric, cis-hydroxyla product, selected on the basis of marketing possibilities tion of alkenes with OsO4 has been conventionally char 20 for a given period, necessarily determines the quantity acterized as taking place via the formation, with the of some other product which may be smaller or larger alkene, of an osmium (VI) intermediate ester complex. than desirable in view of changing marketing require (For a recent review, see, "Osmium Tetroxide Cis Hy ments within that same period. It can, therefore, under droxylation of Unsaturated Substrates', by M. certain circumstances be considered as a disadvantage Schroder, Chem. Rev. Vol 80, pp. 187-213 (1980) here 25 of the aforenoted organohydroperoxide based processes inafter Schroder). that such large quantities of organic alcohols are formed To convert the non-catalytically prepared osmium as co-products, even though under other circumstances (VI) ester complex intermediate to the diol, the interme the formation of two products may well be found ac diate can be hydrolyzed reductively. Reductive hydro ceptable. lysis is conventionally carried out by using alkali metal 30 In contrast, oxygen based hydroxylation systems do sulfites, bisulfites, lithium aluminum hydride, or hydro not produce an oxidant derived alcohol co-product that gen sulfide to yield the corresponding cis-diols together must be disposed of, which can be a significant advan with lower valence forms of osmium which are re tage. moved by filtration. The search has, therefore, continued for ways of It has been observed by Criegee (see Schroder, page 35 improving the rate and/or selectivity of osmium cata 191, Col. 1 11-12) that for non-catalytic cis hydroxyl lyzed oxygen based processes for hydroxylating olefins. ation of alkenes, the rate of formation of the Osmium One step in this direction, is disclosed in commonly (VI) ester complex is greatly increased in the presence assigned U.S. Pat. No. 4,390,739 by R. Austin and R. of tertiary amines such as pyridine. This rate enhance Michaelson. This patent describes a process for the ment is believed to occur via the formation of some type 40 hydroxylation of olefins using oxygen as an oxidant, a of amine Osmium (VI) ester complex (see Schroder catalytically active metal oxide catalyst such as OsO4, page 191, Col. 2). However, enhancement of the rate of and at least one transition metal salt co-catalyst such as the Osmium (VI) ester complex does not necessarily copper bromide. This process can also be conducted in result in an enhancement of the overall hydroxylation the optional presence of a second co-catalyst such as 45 alkali metal halides. Pyridine is disclosed as a suitable rate, since the rate of hydrolysis of the ester complex solvent for this process but no mention is made of any must also be considered. In this regard, it has been noted promoting effect being associated with this solvent that whereas certain osmium ester complexes and amine medium. While the use of the transition metal co ester complexes (e.g. with pyridine) can be hydrolyzed catalyst substantially improves the reaction rate and/or reductively, amine ester complexes are more resistant to 50 selectivity of the hydroxylation reaction, a further im such hydrolysis. (See Schroder page 191, Col. 2, last provement in this process is still being sought. paragraph; and page 193, Col. 1, first paragraph). U.S. patent application Ser. No. 310,217, filed Oct. 9, In contrast to the stoichiometric non-catalytic mode 1981, now abandoned, of common assignee herein by R. of cis hydroxylation with OsO4, the catalytic mode Michaelson and R. Austin discloses the use of various employs a secondary oxidant to oxidatively hydrolyze 55 osmium halide and oxyhalide catalysts in the presence the intermediate Osmium (VI) ester and regenerate the or absence of a wide variety of co-catalysts and an OsO4 which can undergo further reduction by the sub oxidant selected from hydrogen peroxide, organohy strate olefin. A variety of oxidants have been employed droperoxides, or oxygen. Pyridine is disclosed as a suit in conjunction with OsO4 such as H2O2, t-butylhy able buffer for pH control in this application, which pH droperoxide and oxygen. 60 control is required when employing hydrogen peroxide. The use of oxygen as an oxidant has encountered Commonly assigned U.S. Pat. No. 4,314,088 and a considerable difficulty due to the appreciable overoxi continuation-in-part thereof, namely, U.S. Pat. No. dation of the products, particularly at elevated tempera 4,393,253 by R. Austin and R. Michaelson collectively, tures (e.g. 70-80 C.), leading to the formation of keto disclose the use of various halide containing co or acid products. However, if the reaction temperature 65 catalysts in conjunction with osmium tetroxide catalyst is lowered to reduce overoxidation, the reaction rate is and organohydroperoxide oxidants to hydroxylate ole so low that yields of cis-diol are drastically reduced. An fins. The halide containing co-catalysts include alkali additional disadvantage of the use of oxygen oxidant is and alkaline earth metal halides, hydrogenhalides, qua 4,496,778 3 4. ternary hydrocarbyl phosphonium halides, halogens, This yield is extremely low, i.e. 22%, and includes both and transition metal halides. half-acetate and diol. When an equivalent of Example 2 U.S. patent application Ser. No. 399,270 filed July 19, of this patent was conducted, the conversion of hydro 1982, by R. Austin and R. Michaelson is directed to a gen peroxide was found to be 10%, the selectivity to process for hydroxylating olefins in the presence of an diol was 10%, the selectivity to diacetate was 20% and organohydroperoxide oxidant, an osmium containing the diol yield was 1%. Thus, among the major disad catalyst and an organic halogenated hydrocarbon co vantages of the process described in this patent are the catalyst. low selectivities to diol and the corrosiveness of metal Commonly assigned U.S. patent application Ser. No. halides in the presence of glacial acids such as acetic 394,414, filed July 1, 1982 by R. Michaelson and R. O acid. Austin, is directed to the use of carboxylate salts as Japanese Patent Application No. Sho 54-145604, pub co-catalysts for use in conjunction with osmium oxides lished Nov. 14, 1979, is directed to a process for hydrox as a catalyst and organohydroperoxide as oxidant to ylating olefins in the presence of OsO4, a quaternary hydroxylate olefins. ammonium salt such as tetraethylammonium bromide, Commonly assigned allowed U.S. patent application 5 and a peroxide including organoperoxides and H2O2 as Ser. No. 397,997 filed July 14, 1982, now U.S. Pat. No. the oxidant. The use of oxygen as the oxidant is not 4,413,151, by R. Michaelson, R. Austin, and D. White is disclosed nor is the co-presence of co-catalyst I salts as directed to a process for hydroxylating olefins in the described herein disclosed. Selectivities to glycol of presence of a supported osmium containing catalyst, from about 4.5 to about 66% are disclosed. H2O2 oxi optional co-catalysts (e.g. CuBr3) and an oxidant se dant in combination with OsO4 is known as Milas rea lected from hydrogen peroxide, organohydroperoxides gent which can lead to non-selective oxidation of olefins and oxygen. as well as over oxidation. H2O2 is also substantially Commonly assigned U.S. patent application Ser. No. more expensive than oxygen or air. Accordingly, the 420,137 filed Sept. 20, 1982 by R. Michaelson, R. Austin uses of organohydroperoxides as well as H2O2 as oxi and D. White is directed to a process for hydroxylating 25 dants are each associated with their own disadvantages. olefins in the presence of an osmium carbonyl catalyst U.S. Pat. No. 2,214,385 discloses the use of hydrogen optional co-catalysts and an oxidant selected from hy peroxide and a catalytically active oxide, such as os drogen peroxide, organohydroperoxide, and oxygen. mium tetroxide, dissolved in an essentially anhydrous, Commonly assigned U.S. patent application Ser. No. non-alkaline, inert, preferably organic, solvent, to con 440,964, filed Nov. 12, 1982 by R. Michaelson, R. Aus 30 Vert, by oxidation, unsaturated organic compounds to tin, and D. White is directed to a process for hydroxyl useful oxygenated products such as glycols, phenols, ating olefins in the presence of an osmium oxide cata aldehydes, ketones, quinones and organic acids. The lyst, optional co-catalysts and sodium hydroxide as a formation of glycols is achieved by conducting the promoter. reaction at temperatures of between several degrees While all of the above described commonly assigned 35 below 0° C. and 21 C. Such low reaction temperatures patents or patent applications disclose the use of pyri drastically and disadvantageously, reduce the reaction dine as one of many suitable solvents, none of these rate to commercially unacceptable levels. At tempera applications show or suggest either alone or collec tures greater than 21 C., the formation of aldehydes, tively, that any promoting effect can be obtained from ketones, and acids is favored. pyridine when employed in accordance with the pres 40 U.S. Pat. No. 2,773,101 discloses a method for recov ently claimed invention. ering an osmium containing catalyst such as osmium Moreover, to the best of the inventors' knowledge, tetroxide, by converting it to the non-volatile osmium not a single prior art publication shows the use of any dioxide form, distilling the hydroxylation product, tertiary amine as a promoter to enhance the overall rate reoxidizing the osmium dioxide to the volatile osmium of osmium catalyzed cis-hydroxylation of olefins with 45 tetroxide, and then recovering the same by distillation. oxygen. While catalytic cis-hydroxylation of tetra and Suitable oxidizing agents used to re-oxidize the osmium tri-substituted alkenes with t-butylhydroperoxide and dioxide, include inorganic peroxides such as hydrogen OsO4 has apparently been conducted in the presence of peroxide, sodium peroxide, barium peroxide; organic pyridine, the oxidative hydrolysis of such esters has peroxides, such as t-butyl peroxide or hydroperoxide, been found to be particularly slow due to steric consid 50 benzoyl peroxide; as well as other well known oxidizing erations (see, Schroder, page 193, Col. 2, first para agents such as oxygen, perchlorates, nitric acid, chlo graph). rine water and the like. As with other methods of the Notwithstanding the above, the following discussion prior art, the above process yields undesirable by-pro is intended to provide a background of osmium based ducts (see Col. 1, line 55) thus reducing the selectivity of olefin hydroxylation processes. 55 the process. U.S. Pat. No. 3,335,174, is directed to the use of British Patent Specification No. 1,028,940 is directed Group Vb, VI-b and VII metal halides and oxyhalides to a process for regenerating osmium tetroxide from (e.g., OsCl3) as hydroxylation and esterification cata reduced osmium oxides by treatment of the latter with lysts in conjunction with aqueous H2O2 as an oxidant. molecular oxygen in an aqueous alkaline solution. More However, the process for using this catalyst requires the 60 specifically, it is disclosed that when osmium tetroxide presence of lower aliphatic hydrocarbon acids such as is used by itself as an oxidizing agent, or as a catalyst in glacial, formic, acetic and propionic acid as solvents. conjunction with other oxidizing agents, to oxidize Under these conditions the reaction times vary from hydrocarbons the osmium tetroxide becomes reduced, to 4 hours, but at the shorter reaction times it is dis and in its reduced form is less active than osmium tet closed that substantial amounts of epoxide result 65 roxide itself. Consequently, by conducting the oxidation thereby indicating that the reaction proceeds via the reaction in the presence of an alkaline medium and peracid route. The only yield disclosed is obtained in Supplying oxygen to the medium throughout the pro connection with tungsten hexachloride in Example 1. cess, the osmium tetroxide is maintained in a high state 4,496,778 5 6 of activity. The oxidation products disclosed include nitrogen containing compounds referred to herein as not only ethylene glycol from ethylene but also organic cocatalyst II can substantially improve the rate of the acids from such compounds as vicinal glycols, olefins, direct hydroxylation of olefins to their corresponding ketones, and alcohols. While the pH of the alkaline diols, e.g. vicinal diols, in a reaction system which em medium is disclosed broadly for all possible reactions as ploys (a) an osmium compound as a catalyst rather than varying from 7.5 to 12 for purposes of re-oxidizing as a stoichiometric oxidant, (b) a transition metal (i.e. reduced osmium tetroxide, the pH employed in the copper) containing compound as a co-catalyst, and (c) example for preparing ethylene glycol is 9.5. If the pH molecular oxygen as the oxidant to induce oxidative is too high, a wide variety of products are produced as hydrolysis of an osmium-olefin cis-ester intermediate. a result of over oxidation and/or degradation. Thus, the O The present invention represents an improvement over sensitivity of the process to the pH of the medium ne the processes described in commonly assigned U.S. Pat. cessitates rigid pH control which is economically disad No. 4,390,739 and U.S. patent application Ser. No. vantageous. 310,217, filed Oct. 9, 1981, by R. Austin and R. Michael U.S. Pat. No. 4,255,596 is directed to a process for SO. preparing ethylene glycol in a homogeneous single 15 The direct hydroxylation route of the present inven phase reaction medium using ethylbenzene hydroperox tion avoids the formation of an oxirane intermediate ide as the oxidizing agent dissolved in ethylbenzene and that must be hydrolyzed to form the corresponding diol osmium tetroxide as the catalyst. The pH of the reaction and which can lead to undesirable by-products as is the medium is maintained at about 14 by the presence of case of the H2O2-peracid route to olefin hydroxylation. tetraalkyl ammonium hydroxide. A small amount of 20 Furthermore, the catalytic nature of the present in water can dissolve beneficially in the medium to reduce vention is far more cost effective and convenient than by-product formation and improve selectivity to the osmium stoichiometric routes to olefin hydroxylation. glycol. The accelerating effect of co-catalyst II is quite sur U.S. Pat. No. 4,049,724 describes the preparation of prising in the reaction system described herein. For glycols from alkenes and from unsaturated alcohols in 25 example, in stoichiometric osmium oxide based olefin an aqueous system using osmium tetroxide and specify hydroxylation, one is unconcerned with the reoxidation ing stable and water-soluble aliphatic hydroperoxides, of stoichiometric osmium oxidant, since once used up it such as tert-butyl hydroperoxide, while a critical pH of is removed from the reaction system. Consequently, the 8 to 12 is maintained by a suitable combination of alkali rate influencing steps in such reactions are the forma metal buffering compounds. The preparation of propy 30 tion of the osmium oxide-olefin cis-ester intermediate lene glycol utilizing tert-butyl hydroperoxide is exem and the hydrolysis of the ester. In contrast, in an os plified in the patent at a selectivity based on the hydro mium oxide catalyzed reaction system, the osmium peroxide of 45 percent. catalyst must go through repeated cycles of reduction None of the aforenoted patents disclose the osmium and reoxidation. Consequently, the rate of reoxidation containing-co-catalytic system described herein. 35 of the osmium becomes a significant rate influencing See also: U.S. Pat. No. 3,317,592 (production of acids step. Thus, while certain tertiary amines, such as pyri and glycols using oxygen as oxidant, OsO4 as catalyst at dine, are known to accelerate the formation of the cis pH 8-10); U.S. Pat. No. 3,488,394 (discloses hydroxyl ester intermediate in stoichiometric oxidations, it is not ation of olefins by reacting olefin and hypochlorite in known what effect, if any, such amines will have on the the presence of OsO4); U.S. Pat. No. 3,486,478 (dis 40 overall hydroxylation reaction rate of oxygen based, closes reaction of hypochlorite and olefin in an aqueous osmium catalyzed hydroxylations which have been medium and in the presence of OsO4 catalyst to hydrox facilitated by a particular transition metal, i.e., copper, ylate the olefin); U.S. Pat. No. 3,928,473 (hydroxylation co-catalyst. In the environment in which the co-catalyst of olefins to glycols with O2 oxidant, octavalent osmium II rate promoter is employed in the present invention, it catalyst (e.g., OsO4), and borates as promoter); U.S. Pat. 45 has been found that the rate accelerating effect achieved No. 3,931,342 (discloses a process for recovering gly thereby is attributable to interaction with the transition cols from an aqueous solution containing alkali metal metal of Co-catalyst I rather than with the osmium borate and osmium compounds (e.g., OsO4); U.S. Pat. catalyst. This conclusion is based on the observations, No. 3,953,305 (discloses use of OsO4 catalyst for hy described hereinafter in greater detail, that (1) the pro droxylating olefins which is regenerated by oxidizing 50 moting effect is a function of the Co-catalyst II/transi hexavalent osmium with hexavalent chromium and tion metal (i.e., copper) mole ratio, (2) other organic electrochemically regenerating hexavalent chromium); materials conventionally believed to operate as equiva U.S. Pat. No. 4,203,926 (discloses ethylbenzene hydro lent or better promoters (relative to pyridine) in stoi peroxide as oxidant used in two phase system to hydrox chiometric osmium based hydroxylation reactions, and ylate olefins in presence of OsO4 and cesium, rubidium 55 by similar mechanisms, are inoperative, or in fact oper and potassium hydroxides); U.S. Pat. No. 4,217,291 ate as rate inhibitors, in the reaction system of the pres (discloses the oxidation of Osmium (III) or (IV) in an ent invention, and (3) the existence of spectral evidence ionic complex with oxygen and an alkali metal, ammo which indicates the presence of a transition metal (i.e., nium, or tetra (-lower) alkyl ammonium cation to a Cu)-pyridine complex in the reaction mixture, the for valency of greater than --5--organo hydroperoxides); 60 mation of such complexes in general, being well known and U.S. Pat. No. 4,229,601 (discloses the use of cesium, in the literature. Furthermore, the aforedescribed inter rubidium and potassium hydroxides as promoters for action of copper with Co-catalyst II appears to be OsO4 catalyst and t-butyl hydroperoxide oxidant for unique among the transition metals. hydroxylating olefins). Accordingly, in one aspect of the present invention 65 there is provided a process for hydroxylating at least SUMMARY OF THE INVENTION one olefinic compound having at least one ethylenic The present invention resides in the discovery that unsaturation which comprises reacting said olefinic certain heteroaromatic and/or pseudo heteroaromatic compound in the presence of oxygen, water, and a cata 4,496,778 7 8 lyst composition in a manner and under conditions suffi ethylene, propylene, butene-1, butene-2, isobutene, pen cient to convert at least one of said ethylenic unsatura tene-1, pentene-2, hexene, isohexene, heptene, 3-methyl tion directly to it corresponding diol, said catalyst com hexene, octene-1, isooctene, nonene, decene, dodecene, position comprising: tridecene, pentadecene, octadecene, eicosene, doco (a) at least one catalytically active osmium containing sene, tricosene, tetracosene, pentacosene, butadiene, compound; pentadiene, hexadiene, octadiene, decadiene, tridecadi (b) at least one transition metal containing Co ene, eicosadiene, tetracosadiene, cyclopentene, cyclo catalyst I having an identity and in an amount effective hexene, cycloheptene, methylcyclohexene, isopropyl to increase at least one of the rate and selectivity of the cyclohexene, butylcyclohexene, octylcyclohexene, hydroxylation reaction relative to its absence; said tran 10 dodecylclohexene, acrolein, acrylic acid, 1,2,3,4-tet sition metal being copper; and rahydrophthalic anhydride, allyl alcohol, methyl meth (c) at least one Co-catalyst II having an identity and acrylate, styrene, cholestrol, and the like. in an amount effective to increase the rate of the hy The preferred olefins are ethylene, propylene, isobu droxylation reaction relative to its absence and repre tylene, styrene, allyl alcohol and allyl chloride. sented by the structural formulae (XIa and XIb) herein 15 The most preferred olefins are propylene, ethylene, after described. and butenes. In another aspect of the present invention the afore described process additionally employs a halo-source to II. further enhance the rate and/or selectivity of the hy droxylation reaction. Osmium Compound (Catalyst) In accordance with the present invention, it has been DESCRIPTION OF PREFERRED found that the oxidation state of osmium in osmium EMBOOIMENTS catalyst as initially added to the reaction mixture is not In accordance with the present invention, at least one critical to catalytic activity when the appropriate co olefin containing at least one ethylenic unsaturation is 25 catalyst system is employed as described hereinafter, reacted with oxygen in the presence of water and a i.e., any osmium compound as described herein when catalyst composition comprising a catalytically active subjected to hydroxylation conditions as described osmium containing compound, at least one Co-catalyst herein, itself possesses, or is converted under such hy I as described herein, at least one Co-catalyst II as de droxylation conditions to a species which possesses, the scribed herein, and optionally, but preferably, at least 30 capability of catalyzing the hydroxylation of olefins one Co-catalyst III, to convert at least one of said ethyl with oxygen. enic unsaturation directly to its corresponding diol. In view of the above, it is possible to flexibly tailor the identity of the osmium compound and co-catalyst I. system described herein to achieve an extremely effi Olefin 35 cient catalyst system for hydroxylating olefins with Olefins which can be hydroxylated in accordance oxygen. In selecting the particular osmium compound with the present invention contain at least one ethylenic for use in the present invention, the volatility and/or unsaturation and comprise any of the unsaturated ali- . toxicity of the compound, and its activity in the system phatic or alicyclic compounds well known in the art for employed will be taken into consideration. undergoing such hydroxylation reactions. Typically, 40 More specifically, included within the scope of os Such compounds will contain from 2 to about 20 car mium compound (the term "osmium compound' is bons, preferably from 2 to about 10 carbons, and most defined herein broadly to also include osmium metal as preferably from 2 to about 5 carbons. Such compounds well as ionic and neutral complexes of osmium and a may be straight or branched chain, mono-olefinic, di ligand) which can be employed in the process of the olefinic, or polyolefinic, conjugated or non-conjugated. 45 present invention include in their order of preference There may be substituted with such groups as aryl, halogenated osmium compounds, ionic osminum com preferably aryl of from 6 to about 14 carbons, alkyl, pounds, osmium oxides, osmium complexes, osmium preferably alkyl of from 1 to 10 carbons, or aralkyl and carbonyls, and osmium metal. alkaryl wherein the alkyl and aryl portions thereof are Representative halogenated osmium compounds are as described above, as well as with functional groups 50 disclosed in U.S. patent application Ser. No. 310,217, such as hydroxyl, carboxyl and anhydride. filed Oct. 9, 1981 the disclosure of which is herein incor Typical of such olefins are those represented by the porated by reference. structural formula: For example, osmium-halogen containing com pounds include osmium halides and osmium oxy ha 55 lides, and complexes thereof, (all of the above being R2 (I) referred to herein collectively as osmium-halides) such as those represented by the structural formulae: Os(X) (e.g., OsX3, OsX4, and OsX5); Os(OH)x3; OsOX4; wherein R1, R2, R3, and R4, which may be the same or OsO3X2; OsONX4; (M)'OsX6-2; (M), OsO2X4-2; different, are selected from the group consisting of hy 60 M+ Os(OH)X5-1; (M),(OsO4X2-2; (M)'OsO2. drogen; substituted or unsubstituted; alkyl, aryl, alkaryl, (OH)2X2-2; (M), OsNX52; and mixtures thereof: and aralkyl hydrocarbyl groups, said hydrocarbyl wherein X is halogen independently selected from the groups being preferably as defined immediately above; group consisting of F, Cl, Brand I; n is an integer which or any two or said R1-4 groups together can constitute a can vary from 1 to 6 (e.g. 3 to 5), M is a cation including cycloalkyl group typically of from about 4 to about 12, 65 cations of alkali metals, (e.g., Li, Na, K, Rb, Cs, Fr), preferably from about 5 to about 8 carbons. alkaline earth metals (e.g., Be, Mg, Ca, Sr, Ba, Ra), Representative olefins which can be hydroxylated ammonium (i.e., NH4--), tetrahydrocarbyl ammonium and contain at least one ethylenic saturation include: (e.g. (R)4N) and tetrahydrocarbyl phosphonium (e.g. 4,496,778 9 10 (R)4P+) said tetrahydrocarbyl groups being as defined More specifically, the term osmium carbonyl com in connection with Group 5 Co-catalysts III discussed pound is defined herein broadly to also include, in addi below; and n' is a number which is selected in conjunc tion to compounds, ionic and neutral complexes of os tion with the valence of cation M to achieve a neutral mium with at least one carbonyl ligand and optionally complex; preferably n' is 1. other ligands such as phosphines, hydride, halide and Representative examples of such compounds include the like as described hereinafter. OsF3, OsCl3, Osbr3, OSI3, OsF4, OsCl4, OsBra, Osl4, Thus, suitable osmium carbonyl compounds include OsFs, Os(OH)Cl3, Os(OH)F3, OsOF4, OsOCl4, Os(CO)5, Os2(CO)9, Os3(CO)12, Oss(CO)16, Osg(CO)18, OsO3F2, OsONCl4, K2OsCl2Br2I2, (NH4)2(OsP6), Os7(CO)21, and Os3(CO)23. Ca(OsI6, Li2OsO2Cl4), (CH3CH2)4NOs(OH)Cls), O Osmium carbonyl complexes suitable for use as the Mg(OsO4F2, Na2Os(OH)2Cl2, BaOsNCls), osmium carbonyl catalyst include those represented by K2OsNCls), (CH3CH2)4POs(OH)Brs), MgOsNBrs), the formulae: Os(CO)X's-2, Os(CO)2X'4)-2, Os(- Na2OsO2(OH)2Cl2), Ba(OsNCs), K2OsNCls), CO)3X'3)-1, Os(CO)4X-2, and Os(X")(CO). K2OsNBrs), and mixtures thereof. (Y)-(PR'3)d, wherein X" is halogen, preferably bromine, The preferred compounds of this class are those hav 15 X" is independently selected from hydrogen (i.e. hy ing a boiling point at atmospheric pressure of typically dride), cyclopentadienyl (CPD), and halogen (prefera greater than about 130 C., preferably greater than bly bromine), Y is independently selected from NO, about 150 C., and most preferably greater than about NH3, and N2, R' is a hydrocarbyl group independently 175° C. selected from alkyl, typically alkyl of from about 1 to The most preferred compounds are those represented 20 10, preferably from about 1 to 5, most preferably from by the structural formula OsX3 such as OsBr3. about 1 to 3 carbons, aryl, typically aryl of from about In selecting the appropriate halogen for the osmium 6 to about 14, preferably from about 6 to about 10, most halide the order of preference in terms of activity is Br, preferably about 6 carbons, alkaryl and aralkyl wherein Cl, I and F. the alkyl and aryl groups thereof are as defined immedi The compounds having the formula Os(X) can be 25 ately above, “a” and "c' represent numbers of from 0 to prepared by the general methods described in "Ad about 3, "b' represents a number of at least 1, "d" repre vanced Inorganic Chemistry' by Cotton and Wilkinson sents a number of 2 or 3 and the sum of a, b, c, and d is (hereinafter Cotton and Willinson), p. 909 (4th ed. 1980). selected in conjunction with the valence of Os to Compounds having the formula OsOX4 and OsO3X2 achieve a neutral complex. can be prepared by the method described in the "J. 30 Representative examples of suitable osmium carbonyl Inorganic Nuclear Chemistry' by Hepworth and Rob complexes include Os(CO)Cls-2, Os(CO)15-2, Os(- inson, Vol. 4, p. 24 (1957). CO)2Bra)-2, Os(CO)2I4-2, Os(CO)3I3)-1, Os(- Compounds having the formula Os(OH)X3 can be CO)3Cl3)-1 Os(CO)4I-2, Os(CO)4C1)-2, Os(T- prepared by the method described in "Comprehensive 35 CPD)2(CO)(Pdb3)2, OsCl2(CO)(Pdb3)2, Os(CO)3(Pdb3)2, Inorganic Chemistry", Trotman-Dickenson (ed.) vol. 3, OsHCl(CO) (Pdb3)3, Osi(CO)(NO)(Pdb3)2, OshCl(CO)(- p. 1217 (1973). PEt2db)3, Osl2(CO)(Pdb3)2, OshI(CO)(Pdb3)3, and mix Compounds having the formula OsONX4 can be pre tures thereof; "Et' representing ethyl, "d" representing pared by the method described in “Comprehensive phenyl, and 7t-CPD representing pi-bonded cyclopenta Inorganic Chemistry' described above at vol. 3, p. 40 dienyl. 1233. The preferred osmium carbonyl compound is Os3. Compounds having the formula (M)'OsX6-2 can (CO)12. be prepared by the general method described in Cotton The aforenoted osmium carbonyl compounds can be and Wilkinson, p. 919. prepared by conventional methods as described in "In Compounds having the formula (M), OsO2X4)2 45 organic Synthesis'', Vol. 13, p. 92 (F. A. Cotton ed. can be prepared by the general method described in 1972); "Quarterly Reviews”, Vol. 24, p. 498 (1970); and Cotton and Wilkinson, p. 917. "Advanced Inorganic Chemistry', Cotton and Wilkin Compounds having the formula Mt Os(OH)xs)-l son, p. 1000 to 1017 (3rd ed. 1972). can be prepared by the general method described in "Z. Representative osmium oxides include OsO2, OsO3, Anorg. Allgen. Chem' by Krauss and Wilken (hereinaf. SO OsO4, and mixtures thereof. The preferred osmium ter Krauss and Wilken) vol. 137, p. 349 (1924). oxide is OsO4. Compounds having the formula (M)'OsO4X2-2 Representative ionic osmium oxide compounds are can be prepared by the method described in Krauss and described in U.S. Pat. No. 4,217,291 the disclosure of Wilken, vol. 145, p. 151 (1925). which is herein incorporated by reference. These ionic Compounds having the formula (M), OsO2. 55 osmium compounds can be represented by the formula: (OH)2X22 can be prepared by the method described in Cotton and Wilkinson, p. 914. M'OsOy (II) Compounds having the formula (M)'OsNX52 can be prepared by the method described in “Inorganic wherein M' is a cation of an alkali or alkaline earth Synthesis', by E. G. Rochow, vol. 6, p. 204 (1960). 60 metal, ammonium, or tetraalkyl ammonium, preferably The disclosures of all of the above references illus tetraalkyl ammonium in which the alkyl group has from trating the methods of preparation of the aforenoted about 1 to about 5 carbons, and x and y are numbers osmium-halide compounds are herein incorporated by such that 2y-x is the valence of the osmium in any com reference. pound defined by this formula. While the preferred The osmium carbonyl containing compounds suitable 65 ionic osmium compounds of this class are the peros for use herein are described in U.S. patent application mates (M'2OsO5) other ionic osmium compounds such Ser. No. 420,137, filed Sept. 20, 1982, the disclosure of as M'2OsO4 (known as osmates), M'2OsO3, and M'OsO2 which is herein incorporated by reference. can also be employed. 4,496,778 11 12 Representative of osmium complexes include those The use of supported osmium compounds for hydroxyl which form with ligands of PR's (R' being as described ation catalysts is described in U.S. patent application above), amines, nitride, T-bonded cyclopentadienyl Ser. No. 397,997 filed July 14, 1982 the disclosure of (at-CPD), and mixtures thereof. which is herein incorporated by reference. Illustrative osmium phosphine complexes can be rep- 5 Accordingly, the material on which the osmium com resented by the structural formula: pound is supported can be inorganic or organic but must be insoluble in the reaction mixture under reaction con Os(X")(Y)e(PR's)f (III) ditions and be capable of physically and/or chemically wherein X" is independently selected from hydrogen, adsorbing the osmium compound to the extent that it (e.g., hydrido) cyclopentadienyl (CPD), and halogen O retains a catalytically effective amount of the osmium (preferably bromine); Y is independently selected from compound adsorbed thereon. NO, NH3, and N2; R' is hydrocarbyl group indepen The catalyst support, when employed, provides not dently selected from alkyl, typically alkyl of from about only a surface for the osmium compound to adhere, but 1 to about 10, preferably from about 1 to 5, most prefer is also gives physical strength and stability to the same. ably from about 1 to 3 carbons, aryl, typically aryl of The surface area of the support when employed is not from about 6 to about 14, preferably from about 6 to critical and typically can vary from about 0.5 to about about 10, most preferably about 6 carbons, alkaryl and 400, preferably from about 1 to about 200, and most aralkyl wherein the alkyl and aryl groups thereof are as preferably from about 30 to about 100 m2/g. A desired defined immediately above, “d' and “e' are numbers of 2O form of inorganic support is one which has a rough from 0 to about 3, “f” is a number of 2 to 4 (e.g. 2 to 3) enough surface to aid in retaining the catalyst adhered and the sum of d, e, and f is selected in conjunction with thereto during handling and under reaction conditions. the valence of Os to achieve a neutral complex. The support may vary in size but typically is from about Representative examples of suitable osmium phos 3 to about 400, preferably from about 5 to about 200, phine complexes include Osha(N2)(Pdb3)3; Osh(Pdb3)4; most preferably from about 6 to about 100 mesh in the OsCl2(Pdb3)3; OsCl3(NO)(Pdb3)2; OsCl(NO)(Pdb3)2; 25 Tyler Standard screen size. Support particles as large as OsCl2(NH3)(PEt2(b)3; Os(tr-CPD)2(NH3)(Pdb)2, and 1 inch in diameter are satisfactory. mixtures thereof; "Et' representing ethyl, "d" repre Supports much smaller than 325 to 400 mesh nor senting phenyl, and 7t-CPD representing pi-bonded mally cause an undesirable pressure drop in the reactor. cyclopentadienyl. The support material is not necessarily inert, that is, Illustrative osmium amine complexes include aro 30 the particular support may cause an increase in the matic amine complexes illustrated by Os(bipy)3+2 catalyst efficiency by its chemical or physical nature or wherein bipy is 2,2'-bipyridine, and Os(NH3)5X)+2 both, but should not adversely influence the hydroxyl wherein X is halogen, preferably Br. ation reaction. Moreover, the support may impart cata Illustrative osmium nitride complexes include 35 lytic activity to an otherwise catalytically inactive, or OsO3N); KOsO3N); and OsO3NC(CH3)3. substantially inactive, material in the absence of the Illustrative T-CPD complexes include Os(T-CPD)2. support such as in the instance of osmium metal. Methods for preparing the aforedescribed osmium The amount of osmium compound adsorbed on the complexes are conventional and are summarized in support is any amount effective to increase the rate Cotton and Wilkinson "Advanced Inorganic Chemis 40 and/or selectivity of the hydroxylation reaction relative try' pages 1000-1017 (3rd ed. 1972). to the absence of the osmium compound. Thus, while The osmium containing compounds are employed in any effective amount may be adsorbed on the support, amounts effective to catalyze the hydroxylation reac such effective amounts typically will be from about 0.01 tion. Thus while any effective amount of osmium cata to about 75, preferably from about 0.05 to about 20, lyst will suffice, it is contemplated that such effective 45 most preferably from about 0.1 to about 10.0%, by amounts constitute, when the osmium compound is in weight, based on the combined weight of osmium com unsupported form, a ratio of the moles of osmium in the pound and support. osmium compound to moles of ethylenic unsaturation The amount of supported osmium catalyst employed to be hydroxylated in contact with said osmium com during hydroxylation will likewise be any amount effec pound of typically from about 1X 10.1:1, to about 50 tive to increase the rate and/or selectivity of the hy 1 x 10-10:1, preferably from about 1 x 10-2:1 to about droxylation reaction relative to the absence of the Sup 1X 10-6:1, and most preferably from about 1 x 10-2:1 ported catalyst. The most convenient way to express to about 1 x 10-5:1. the amount of supported osmium catalyst (i.e., osmium Alternatively, such amounts may be expressed as compound--support) having the aforedescribed varying from about 1 to about 10,000, preferably from 55 amounts of osmium compound adsorbed thereon is as a about 10 to about 5,000, and most preferably from about ratio of the weight of the supported osmium catalyst in 50 to about 1,000 ppm, based on the total weight of contact with the weight of reaction mixture at any liquid reaction medium including the weight of olefin given time during the reaction. and any other additives, solvent, or co-catalysts. Accordingly, while any effective amount of sup While it has been determined that the hydroxylation 60 ported osmium catalyst may be employed, it is contem reaction is first order in the osmium compound, the high plated that such effective amounts constitute a ratio of cost of osmium will generally militate against using parts by weight of supported catalyst to parts by weight large amounts of osmium in the reaction system. of reaction mixture in contact therewith of typically III from about 1:0.8 to about 1:20, preferably from about 65 1:1 to about 1:10, and most preferably from about 1:1 to Support about 1:4. The aforedescribed osmium containing compounds Representative Supports include alkaline earth metal can be employed in supported or unsupported form. oxides including MgO, CaO, BaO, BeO and SrO; 4,496,778 13 14 Sc2O3; Y2O3; oxides of the Lanthanide series of ele nylbenzene (DVB). The ester groups are hydrolyzed to ments represented by the formula Ln2O3, wherein Ln produce the functional acid group. represents a lanthanide element (i.e., atomic number 58 Representative of strong acid cation exchange resins to 71); alumina (Al2O3); silica (SiO2); silica gel; silica include sulfonated co-polymers of styrene and DVB. alumina; silicon carbide; titania (TiO2); titania-silica; Sulfuric acid, sulfurtrioxide, and chlorosulfonic acids carbon; activated carbon; Al2O3. B2O3, SiO2. B2O3, and can be used for such sulfonation. mixtures thereof alkaline earth metal orthosilicates Representative of strong-base anion exchange resins such as Ca2SiO4, Mg2SiO4; heteropolyanions such as include those based on a styrene-DVB co-polymer hav heteropoly tungstates, heteropoly molybdates (e.g., ing an amine functional group, pendant from the aro Na3PMO 12O40) and the like; and insoluble halogen salts 10 matic portion of the co-polymer. The base strength of such as Hg22, HgI2, and Pb2. the resin can be varied by varying the nature of the Another class of suitable supports include ionic mate amine functional group from primary to tertiary. The rials onto which the osmium compound can be ad counter ion, prior to incorporation of the osmium com sorbed. Included within the scope of ionic supports are pound, for the acid exchange resin is preferably sodium, zeolites, and ionic polymeric compounds. 15 and for the base-exchange resin, hydroxyl, although any Suitable zeolites which can function as supports in of the conventional counter ions associated with com accordance with the present invention are exemplified mercially available ion exchange resins can be em by crystalline aluminosilicate zeolites, preferably Zeo ployed. Other acid or base functional groups can be lites of the faujasite structure. Typically, such faujasite incorporated into the pendant aromatic groups of the materials possess a SiO2:Al2O3 mole ratio in the range of 20 resin tailored specifically to react, complex with, or about 2 to about 8 and characteristically have pore facilitate adsorption of, the osmium containing com diameters in excess of 6 angstroms, which is appropriate pound. for admission of reactants, and to allow exit of the hy Furthermore, the functional groups of the base ion droxylated product. The X- and Y-type Zeolites are exchange resin can be partially or completely exhausted 25 (i.e., exchanged) with halide ions which can perform suitable for use as supports herein, with the X-type the function of the halide co-catalysts described herein. being preferred. Type X zeolite has a typical oxide In this way, the base ion exchange resin support, sup formula: Na2O:Al2O3:2.5 SiO2:6H2O although the mole ports not only the osmium compound but also the co ratio of SiO2:Al2O3 can typically vary from about 2:1 to catalyst halide species resulting in an insolubilized cata about 3:1. Type Y zeolite has a typical oxide formula: 30 lytic and co-catalytic system. Na2O:Al2O3:4SiO2:8H2O although the mole ratio of Representative commercial ion-exchange resins in SiO2:Al2O3 can typically vary from about 3:1 to about clude those sold under the following tradenames: DO 6:1. Type L zeolites, natural faujasite materials and WEXTM available from Dow Chem. Co.; DUOLI mordenites are examples of other zeolites having appro TE TM available from Diamond Shamrock; AMBER priate pore size and structure for use as a support herein. 35 LITE available from Rohm and Haas Co.; and NAL In general, zeolites having suitable properties can be CITE TM available from Nalco Chemical Co. utilized, whether obtainable as natural materials or pre The osmium compound is adsorbed on the support by pared synthetically, and can be obtained from commer any way capable of achieving physical and/or chemical cial sources or prepared by appropriate laboratory crys adsorption of the latter by the support. Thus, adsorption tallization procedures. 40 methods are used which result in retention of the os The ionic and porous nature of zeolites permits incor mium compound in or on the support, and various mate poration of the osmium compound therein by conven rials and procedures have been found suitable for this tional ion exchange and/or impregnation procedures as purpose. described hereinafter. Similar considerations also apply For example, an inorganic non-ionic support, e.g., with respect to ionic polymer supports. 45 MgO, can be suspended in a suitable solvent together Polymeric ionic support materials typically are em with the osmium compound, preferably a saturated or ployed in porous solid form such as beads, powders, supersaturated solution of the osmium compound, at granules, and the like. Suitable polymeric supports are room temperature and stirred for a period of from about stable to hydroxylation reaction conditions, and suffi 0.1 to about 72, preferably from about 0.5 to about 48, ciently adsorptive toward the reaction mixture to 50 most preferably from about 0.5 to about 24 hours. The achieve good contact therewith with the osmium cata suspension is then filtered and the recovered solids lytic sites present therein. Accordingly, the polymer rinsed, with a suitable solvent. If the support and os must be sufficiently inert and rugged when in contact mium compound are both dissolved, the solvent can be with the hydroxylation reaction mixture to be resistant evaporated and the solids recovered after adsorption of to the reaction mixture and easily separated therefrom; 55 the osmium compound by the support. and not be abraded, dissolved, decomposed or con The suspension and/or solution of the support and verted into a soft pulpy gel difficult to separate from the osmium compound can be heated to elevated tempera reaction mixture. tures although this is not essential. Representative classes of suitable ionic polymer sup Suitable solvents and/or suspending media for the ports include conventional weak and preferably strong, 60 aforedescribed purposes include water, alcohols, ke acid (cation) or base (anion) exchange resins. Ion ex tones, ethers, aliphatic hydrocarbons, aromatic hydro change resins typically comprise as a back-bone poly carbons, halogenated hydrocarbons, carboxylic acids mer, a polymer crosslinked with a difunctional mono and their derivatives such as amides. mer, to which is attached functional acid or base groups Other adsorption methods include vapor phase depo exchanged with various cations or anions (i.e., counter 65 sition, electrodeposition, and sublimation. ions) respectively. Representative of weak-acid cation When employing ionic supports, which typically exchange resins include those based on polymers of possess pores capable of retaining the osmium com acrylic or methacrylic acid esters crosslinked with divi pound, the adsorption method employed can utilize an 4,496,778 15 16 ion-exchange procedure which results in valence-bond ing of the osmium compound with the support and/or O (IV) impregnation techniques. For example, when employing zeolites or acid cation (Rs-C-O exchange resins, conventional ion exchange procedures can be employed to replace the support counter ion wherein R5 is selected from the group consisting of with a cationic osmium compound. Such ion exchange substituted and unsubstituted: alkyl, typically about C1 can be effected, for example, with solutions of cationic to about C10 alkyl, preferably about C1 to about C5 osmium species as described hereinabove, including alkyl, and most preferably about C1 to about C3 alkyl; osmium salts, such as osmium halides, nitrates, or sul O cycloalkyl, typically about C4 to C20 cycloalkyl, prefer fates. The weight ratio of osmium to support will vary ably about C5 to C15 cycloalkyl, and most preferably depending on the number of anionic sites available on about C6 to C10 cycloalkyl; and aralkyl, typically aralkyl the support. However, it is preferable to maximize this wherein the aryl group thereof is as defined in connec ratio so that as many as possible anionic sites bond with tion with Ar of structural formula V below and the the ionic osmium compound. 15 alkyl group thereof is as defined immediately above; Similar exchange procedures can be employed with said R5 substituents including hydroxyl; halide (i.e., F, base anion exchange resins, with the exception that an Cl, Br, and I); ether groups, typically ether groups rep anionic osmium compound species as described herein resented by the structural formulae -O-R6, and -R- above is employed to effect the exchange. 7-O-R6 wherein R5 and R7 are independently se Adsorption methods can also be employed which lected from the group consisting of alkyl, typically result in impregnation of the porous ionic support with about C1 to about C10 alkyl, preferably about C1 to the osmium compound. Thus, the osmium compound about C5 alkyl and most preferably about C1 to about can conveniently be impregnated into the support by C3 alkyl; and ester groups, typically ester groups, repre utilizing a solution of such osmium compound as a slur sented by the structural formulae rying medium for support particles or as an impregnat 25 ing medium to be adsorbed into the support. The media for incorporating the osmium compound do not neces sarily have to completely dissolve the same and in fact may often contain suspended solids. The supported osmium catalyst is adaptable for use in 30 the various physical forms which are commonly used in a contact bed, or as a coating material on monolithic structures generally being used in a form to provide wherein R8 and R9 which may be the same or different high surface area. The supported catalyst, can if de are as defined in connection with R6 and R7; sired, be composited with various binders which do no t 35 (c) aryloate anions, typically aryloate anions repre adversely affect the catalyst or the reactions in which sented by the structural formula: the catalyst is to be employed. Depending on the choice of osmium compound and (V) support, the adsorption will be chemical and/or physi (Ar-C-O- cal. 40 For example, osmium carbonyls are believed to react wherein Ar is selected from the group consisting of with alkaline earth supports such as MgO to form oxy substituted and unsubstituted: aryl, typically C6 to about gen bonded clusters. Osmium halides or oxy halides are C14 aryl, preferably C6 to about C10 aryl (e.g., C6 aryl) believed to react with metal oxide supports to form and alkaryl, typically alkaryl wherein the alkyl group is oxygen bonded compounds. Osmium oxides are be 45 as defined above in connection with R5 being alkyl, and lieved to react with metal oxide supports to form os the aryl group thereof is as defined above, and wherein mium oxyanions. Valence bonding of ionic osmium said substitutents on the Ar group are as defined above compounds with ion-exchange resins has already been in connection with R5; discussed. 50 (d) aryolate anions, typically aryolate anions repre IV sented by the structural formula: Co-catalyst System (Arror (VI) (a) Co-catalyst I Co-catalyst I is a term used to refer to at least one 55 wherein Ar is as described above in connection with organic or inorganic transition metal, i.e., copper, con structural formula IV, and preferably is aryl; and taining compound. Such copper compound will typi (e) pseudohalide anions, defined herein to be selected cally be employed as a salt having an anion and a cation, from the group consisting of SNC, CN-, SeCN-, wherein the anion of said salt includes halide, pseudo TeCN, OCN-, and CNO-; and halide, carboxylate, aryloate, and aryolate and other 60 (f) anions selected from the group consisting of anions described hereinafter. NO3, R10S, HS, R10Se-, HSe-, HTe-, and The cation transition metal of said Co-catalyst I salts R10Tel, R10 being alkyl typically about C to about is copper. C10 alkyl, preferably C1 to C5 alkyl. More specifically, the anion of Co-catalyst I includes: In short, the Co-catalyst I, when employed as a salt, (a) halide ions, in their order of preference as follows: 65 can be a single salt, or a mixture of salts and said salts bromide, chloride, iodide, fluoride; can comprise any of the aforenoted transition metal (b) carboxylate anions, typically carboxylate anions cations associated with any of the aforenoted group represented by the structural formula: (a)-(f) anions. 4,496,778 17 18 Representative examples of Co-catalyst I salts include Co-catalyst II is conveniently described with refer CuF2, CuBr2, CuI2, CuCl2, CuI, CuCl, CuBr, CuF, ence to pyridine. For example, pyridine can be repre copper acetate, copper naphthoate, copper benzoate, sented by the following structural formula: copper propanoate, copper nitrate, copper 4-ethylben zoate, copper 4-butylbenzoate, copper decanoate, cop per hexanoate, copper phthalocyanine, copper 2-(me 1 (VII) thoxymethyl) acetate, copper 3-(ethoxy)propanoate, copper 4-(propoxy carbonyl)-butanoate, copper 3-(pro pyl carbonyl oxy)propanoate, copper 2-(methyl car bonyloxy methyl)acetate, copper 4-(ethoxy carbonyl 10 methyl)butanoate, copper 4-(ethoxy methyl) benzoate, copper 3-(propoxy) naphthoate, copper 4-(ethoxy car Pyridine performs as an excellent rate promoter of, for bonyl) benzoate, copper 2-(hydroxy)acetate, copper example, an osmium catalyzed CuBr2 co-catalyzed, 2-chloro propanoate, copper 4-(bromo) benzoate, cop oxygen based olefin hydroxylation system. It is believed per 4-(hydroxy) benzoate, copper phenolate, copper 15 that one of the essential features of the pyridine mole naphtholate, copper 4-chloro phenolate, copper 5-(hy cule responsible for the observed promoting effect is a droxy) naphtholate, Cu(CN)2, Cu(SeCN)2, Cu(TeCN)2, tertiary amine nitrogen group located within and form Cu(OCN)2, Cu(CH3S)2, Cu(CH3CH2S)2, Cu(HS)2, ing a part of an aromatic nucleus. However, it has also Cu(CH3-CH2-CH2-Se)2, Cu(HSe)3, Cu(HTe)2, been found, that as the hydrogens located at the 2 and 6 Cu(CH3Te)2, and mixtures thereof. 20 positions of the pyridine ring are successively replaced The preferred Co-catalyst I salts include copper: with more bulky substituents, e.g. a methyl group, the bromide, chloride, iodide, nitrate and acetate. promoting effect relative to pyridine is decreased due, it The amount of Co-catalyst I employed in the reaction is believed, to steric hinderance about the tertiary nitro system is related to the amount of osmium in contact gen atom. Thus, it is believed that steric freedom about with reaction mixture. Thus, while any amount of Co 25 at least one of tertiary nitrogens of Co-catalyst II is an catalyst I effective to enhance the rate and/or selectiv important consideration in selecting the identity of the ity of the hydroxylation reaction relative to its absence co-catalyst. can be employed, it is contemplated that such effective The requirement of the absence of a primary or sec amounts constitute a mole ratio of osmium to the transi ondary nitrogen is best illustrated with reference to tion metal of Co-catalyst I in the reaction system in 30 imidazole represented by the following structural for contact with the olefin, of typically from about 1:1000 mula: to about 1:1, preferably from about 1:500 to about 1:5, and most preferably from about 1:50 to about 1:10. (VIII) (b) Co-catalyst II 35 Co-catalyst II is defined herein to be at least one compound capable of improving the rate of the hydrox ylation reaction when employed in the presence of the osmium compound catalyst, at least one Co-catalyst I, As shown in the Examples, imidazole is not an effective and oxygen. 40 rate promoter due, it is believed, to the presence of a Suitable Co-catalyst II is characterized by: (1) the secondary nitrogen at the number 1 position in the ring. possession of at least one tertiary nitrogen; (2) a When this nitrogen is converted to a tertiary nitrogen heteroaromatic or pseudoheteroaromatic ring structure; by substitution of a methyl group for the replaceable (3) the absence of primary or secondary nitrogens in the hydrogen, however, rate enhancement is imparted to aforenoted ring structures; (4) appropriate steric config 45 the compound. The disadvantageous consequences of uration of any substituents located on the aforenoted the presence of a secondary or primary nitrogen is not ring structures; (5) the absence of nitrogen atoms, in entirely understood, but it is believed that such nitro fused bicyclic or tricyclic heteroaromatic ring struc gens may be too basic, impart too great an ability to the tures, having a configuration within said ring structures Co-catalyst II to coordinate with the transition metal of sufficient to enable a bidentate ligand relationship to 50 Co-catalyst I to the extent that it effectively prevents exist with the transition metal of co-catalysts; and (6) the transition metal from performing its intended func the absence of a 1,3- or 1,4- positional configuration tion, and/or is too readily oxidized in-situ under reac between any two tertiary nitrogens present in said ring tion conditions. StructureS. Regarding the limitations of heteroaromatic fused A heteroaromatic ring system or nucleus is defined 55 bicyclic or tricyclic ring structures of Co-catalyst II, it herein to be one in which at least one carbon atom that has been found that 4,5-diazaphenanthrene and 1,8- is a member of an aromatic ring of an aromatic com diazanaphthalene are not effective rate promoters. Both pound is replaced with a heteroatom (e.g. nitrogen) and of these compounds possess two tertiary nitrogens in a the resulting compound contains the maximum number fused bicyclic and tricyclic heteroaromatic ring system, of conjugated double bonds compatible with the va 60 respectively as follows: lency restrictions imposed by the heteroatom. A pseudoheteromatic ring structure or nucleus is defined herein to be a 5 carbon membered ring system (IX) wherein at least one of the carbons present therein is replaced with a heteroatom (e.g. nitrogen) and the re 65 sulting compound contains the maximum number of conjugated double bonds compatible with the valency 1,8-diazanaphthalene restrictions imposed by the heteroatom. 4,496,778 19 20 -continued -continued (X) Z8 N (XIb)

2.9 ' 7 5 n Y R2 wherein in structural formula (Xa): Z2 to Zó represent, 4,5-diazaphenanthrene to independently, a methylidyne group (-CH=), a substi tuted methylidyne group (ECR 11), or a tertiary nitro The particular location of the two nitrogens is believed to be such that each nitrogen pair is capable of collec gen group (-N=), all within a heteroaromatic nucleus tively interacting with the transition metal of Co containing nitrogen as the heteroatom therein. The catalyst I as a bidentate ligand, the 1,8-diazanaphthalene substituent R11 of Z2 to Zé is selected from the group configuration permitting the formation of a 4 member 15 consisting of hydroxy; alkyl, typically about C1 to C10 ring with a central transition metal ion, and the 4,5- alkyl, preferably about C1 to C5 alkyl, and most prefera diazaphenanthrene permitting the formation of a 5 bly about C1 to C3 alkyl; aryl, typically about C6 to C14 membered ring with a central transition metal ion. The aryl, preferably Ce to C10 aryl, and most preferably C6 functioning of the Co-catalyst II as a bidentate ligand is 20 aryl; aralkyl and alkaryl wherein the alkyl and aryl believed to sufficiently disrupt the interaction of the portions thereof are as described immediately above; transition metal with other components in the reaction either groups or ester groups wherein said ether and mixture, that the rate enhancement is lost. Thus, it is ester groups are as described in conjunction with R5 of believed that while Co-catalyst II must possess the abil structural formula (IV) above, said R11 substituents ity, complex to some extent, (e.g. as a monodentate 25 preferably being inert under reaction conditions. In ligand) with the transition metal of Co-catalyst II, the addition, any two R11 groups located on adjacent car stability of the complex should not be so great (e.g. as in bons of said Z2 to Z5 groups of structural formula (XIa) bidentate ligands) that the transition metal is, in practi together can constitute part of a monocyclic, or fused cal effect, removed from interaction with the remainder bicyclic ring system, which partial ring system is: (a) of the components of the reaction mixture. Note that for 30 fused tricyclic heteroaromatic ring systems, it is not aromatic, or heteroaromatic in nature said heteroatom considered possible for such compounds to act as tri being nitrogen and (b) completed by, and fused with, dendate ligands, although, if possible, such an occur parent structure (XIa) above, through said adjacent rence would also sought to be avoided. In accordance carbons of the Z2 to Z5 groups. Moreover, the replace with the above theory, and under the replacement no 35 able hydrogens of the multicyclic ring system incorpo menclature system of carbocyclic systems described in rating any two of said R11 groups together, can be sub "Nomenclature of Organic Compounds' ed. Fletcher, stituted with hydroxy, alkyl, aryl, aralkyl and alkaryl J., Dermer, O., Fox, R., Advances in Chemistry Series groups as defined above. 126, pp. 49 et.seq. (1974), 1,8-diazanaphthalene, 4,5- In structural formula (XIb), Z7 to Z9 independently diazaphenanthrene, and 1,9-diazaanthracene com 40 represent a methylidyne group (-CH-), or a substi pounds and their derivatives are considered ineffective tuted methylidyne group (=ECR'11) wherein R11 is in co-catalysts. dependently selected from the group consisting of alkyl, Regarding the limitation relating to the relationship between any two tertiary nitrogens present in the ring aryl, aralkyl, and alkaryl as described in conjunction Structure, it has been found that in the series of diaza 45 with R11. The substituent R12 of formula (XIb) is se benzene isomers, only 1,2-diazabenzene is an effective, lected from the group consisting of alkyl, aryl, aralkyl, albiet slightly effective, rate promoter while 1,4- and and alkaryl as described in conjunction with R1 of 1,3-diazabenzenes actually inhibit the hydroxylation formula (Xa), preferably C1 to C5 alkyl. reaction. The reason for this occurrence is not entirely Furthermore as discussed above, in order to impart a understood, but has led to the conclusion that such 1,4- 50 rate promoting effect to the Co-catalysts II described by and 1,3-relationships between tertiary nitrogens present formula (XIa), said formula is also functionally limited in a mono-, bi- or tri-cyclic fused heteroaromatic ring by the proviso that in any cyclic ring system defined system should be avoided. Thus, for example, typically thereby which contains more than one tertiary nitrogen, in a bi-cyclic ring system a maximum of 3, preferably 2, 55 the relative configuration between any of said nitrogens most preferably 1, tertiary nitrogen(s) will be present within said cyclic ring system: (i) excludes a 1,3- and therein. Unsuitable diazanaphthalenes include 1,3-, 1,4- 1,4-positional relationship; and (ii) prevents Co-catalyst isomers thereof. II from acting, under reaction conditions, as a bidentate In view of the above functional requirements, suitable ligand in conjunction with Co-catalyst I. Co-catalysts II for use in the present invention can be 60 Preferably at least one, most preferably both, of said represented by at least one of the structural formulae: Z2 and Z6 groups of formula (XIa) are methylidyne. Likewise, preferably at least one, most preferably both, (XIa) of said Z7 and Z8 groups of formula (XIb) are methylid 65 yne. Representative compounds suitable for use as Co catalyst II are provided at Table 1 herein. The most preferred Co-catalyst II is pyridine. 4,496,778 21 22 contemplated to employ Co-catalyst II as solvent for N the reaction system, if one seeks a rate promoting effect 2- N attributable thereto. Accordingly, the reaction mixture will comprise typi CN 1. cally less than 50%, preferably less than 15%, and most Azabenzene 2,3-diazanaphthalene preferably less than 5%, by weight of Co-catalyst II, (Pyridine) (Phthalazine) based on the total weight of the liquid contents of the

reaction mixture. N (c) Co-catalyst III 2- CH3 10 Co-catalyst III is a term used herein to describe at N least one material, typically employed in an organic or 2-methyl-l-azabenzene inorganic salt form, which functions in conjunction with Co-catalysts I and II to further improve the rate N N and/or selectivity of hydroxylation reaction. The use of t- S N 15 Co-catalyst III is optional although preferred, particu larly with respect to a halide containing Co-catalyst III. N 21 Suitable promoters or Co-catalysts III include alkali 1,2-diazanaphthalene (e.g., Li, Na, K, Rb, Cs, and Fr), and alkaline earth CH3 (Cinnoline) 4-methyl-l-azabenzene metal (e.g., Be, Mg, Ca, Sr, Ba, and Ra): halides, oxides (4-methylpyridine) 20 and/or hydroxides, carboxylates, aryloates, aryolates and pseudo halides; tetra hydrocarbyl ammonium: hy N sa droxides, halides, carboxylates, aryloates, and aryolates; e CH3 N tetra hydrocarbyl phosphonium: hydroxides, halides, carboxylates, aryloates, aryolates; hydrogen halides; N 21 25 halogenated hydrocarbons such as alkyl, aryl, aralkyl, 2-azanaphthalene CH3 (Isoquinoline) alkaryl and cycloalkyl halides; Group III-b (i.e., B, AL, 2,4-dimethyl-1-azabenzene Ga, In, Tl), IV-b (i.e. Si, Ge, Sn, Pb), V-b (i.e., N, P, As, Sb, Bi) and VI-b (i.e., S, Se, Te, Po) halides; and the N N halogens F2, Cl2, I2, Br2. e 30 More specifically, suitable alkali and alkaline earth metal halide Co-catalysts III (referred to herein as CH3 Cl CH3 l N CH3 Group I Co-catalysts III) include the Li, Na, K, Rb, and 3,5-dimethyl-l-azabenzeneN CH3 Cs bromides, iodides, chlorides and fluorides; and Mg, (3,5-dimethylpyridine) 1-methylimidazole Ca, Sr, and Ba, bromides, iodides, chlorides, and fluo 35 rides and mixtures thereof. Preferred Group 1 co N N catalysts include the Na, K, Rb, Cs, Mg and Cahalides, CH3-1 CH3 particularly bromides. ON l N CH3 Suitable alkali and alkaline earth metal hydroxide or 2,6-dimethyl- 1-azabenzene CH3 oxide co-catalysts (referred to herein as Group 2 co (2,6-dimethylpyridine) 1,2-dimethylimidazole 40 catalysts III) include LiOH, NaOH, KOH, RbCH, CsOH, Ca(OH)2, Ba(OH)2, Mg(OH)2, the correspond ing oxides thereof, and mixtures thereof. 21 Preferred Group 2 Co-catalysts III include the Na, K, Rb, Mg and Ca hydroxides. 21 N 45 Suitable alkali and alkaline earth metal: carboxylate, 4-phenyl-l-azabenzene aryloate, and aryolate co-catalysts (referred to herein as (4-phenylpyridine) N N. Group 3 Co-catalysts III) include those which possess 2,7-diazaphenanthren as anions respectively: (a) carboxylate anions represented by the structural 50 formula: 2- n C (XII) 1,2-diazabenzene (Pyridazine) 55 wherein R'12 can be substituted or unsubstituted: alkyl, The amount of Co-catalyst II employed in the reac typically alkyl of from about 1 to about 10 carbons, tion system will affect the performance thereof. While preferably about 1 to about 5 carbons, and most prefera any amount effective to increase the rate of the hydrox bly about 1 to about 3 carbons, cycloalkyl, typically ylation reaction can be employed such amounts will 60 cycloalkyl of from about 4 to about 20, preferably from generally constitute a ratio of moles of Co-catalyst II to about 5 to about 15, and most preferably from about 6 to the moles of the transition metal employed as Co about 10 carbons, or aralkyl, typically aralkyl wherein catalyst I of typically from about 1:1 to about 15:1, the aryl group thereof is as defined in connection with preferably from about 2:1 to about 10:1, and most pref Ar"- of structural formula (XIII) below and the alkyl erably from about 3:1 to about 8:1. 65 group thereof is as defined immediately above; said R'12 If too much Co-catalyst II is employed (e.g. solvent substituents including: hydroxy; halide (i.e., F, Cl, Br, amounts) in the reaction mixture, no effect on reaction and I); ether groups represented by the structural for rate is observed relative to its absence. Thus, it is not mulae -O-R6 and -R7-O-R6 wherein R5 and R7 4,496,778 23 24 are independently as described in connection with for Preferred Group 4 Co-catalysts III include the Na, K, mula (IV) above; and ester groups represented by the Rb and Cs thiocyanates. structural formulae: Tetrahydrocarbyl ammonium or phosphonium Salt co-catalysts (referred to herein as Group 5 Co-catalysts O O O O III) possess a cation and an anion. The respective cati I ons can be represented by the respective structural formula (R)4N+ and (R)4P+ wherein R is a hydro carbyl group independently selected from the group wherein R8 and R9 which may be the same or different consisting of substituted and unsubstituted: alkyl, typi are as defined in connection with formula (IV) above 10 cally alkyl having from about 1 to about 30 carbons, and mixtures thereof. preferably from about 1 to about 20 carbons, and most (b) aryloate anions represented by the structural for preferably from about 1 to about 10 (e.g. 1-5) carbons, mula: aryl, preferably aryl having from 6 to 14 carbons, and most preferably from 6 to about 10 carbons, and alkaryl O (XIII) 15 and aralkyl wherein the aryl and alkyl groups thereof are as defined immediately above; said R substituents being as defined in connection with the substituents of wherein Ar' is selected from the group consisting of R12 described above. Accordingly, the term hydro substituted and unsubstituted: aryl, typically aryl of carbyl is intended to include both substituted and unsub from about 6 to about 14 carbons, preferably from about 20 stituted groups, and mixtures thereof. The anion of the 6 to about 10 carbons, (e.g., 6 carbons), and alkaryl, Group 5 Co-catalysts III are selected from the group typically alkaryl wherein the alkyl group is from about consisting of hydroxy, halide, pseudo halide, carboxyl 1 to about 6 carbons, preferably from about 1 to about ate, aryloate and aryolate, said pseudo halide, said car 3 carbons, and the aryl group thereof is as defined im boxylate, aryloate, and aryolate anions, being as defined mediately above, and wherein said substituents on the 25 above in connection with the anions of the alkali and Ar' group are as defined above in connection with R'12; alkali metal Co-catalysts III described above. and Illustrative examples of such Group 5 Co-catalysts III (c) aryolate anions represented by the structural for include tetramethylammonium bromide, tetraethyl mula: phosphonium chloride, tetradecylphosphonium bro 30 mide, tetraphenylammonium chloride, tetraphenyl phosphonium bromide, dimethyldiethylammonium io (Ar'-O- (XIV) dide, methyltriethylphosphonium chloride, tet rabutylammonium chloride, phenyltrimethylam wherein Ar' is as described above in connection with monium bromide, phenyltrimethylphosphonium chlo structural formula (XIII) and preferably is aryl. 35 ride, phenyltriethylammonium iodide, phenyltriethyl Illustrative examples of such Group 3 Co-catalysts III phosphonium chloride, tetraethylammonium hydrox include: sodium acetate, potassium acetate, calcium ide, tetrabutylammonium hydroxide, tetraethylphos acetate, cesium acetate, magnesium acetate, potassium phoniumhydroxide, phenyltriethylammonium hydrox ethanoate, sodium propanoate, magnesium butanoate, ide, phenyltrimethylphosphonium hydroxide, tetrae strontium pentanoate, sodium benzoate, potassium ben 40 thylammoniumacetate, tetrabutylphosphonium acetate, zoate, magnesium benzoate, calcium benzoate, sodium phenyltriethylammonium acetate, phenyltrimethyl naphthoate, potassium naphthoate, beryllium naphtho phosphonium acetate, tetraethylammonium benzoate, ate, sodium 4-(6-methyl-2-naphthyl)-pentanoate, potas phenyltrimethylphosphonium benzoate, phenyltrie sium 3-(7-methyl-1-naphthyl)-propanoate, magnesium thylammonium naphthoate, tetraethylammonium phe 2-(4-propyl-1-benzyl)-ethanoate, calcium phenolate, 45 noiate, tetrabutylphosphonium naphtholiate, tetra-2- sodium naphtholate, potassium naphtholate, sodium (methoxy)ethylphosphonium chloride, tetra-4-(propox 3-(ethoxy)-propanoate, potassium 4-(propoxycarbonyl) ymethyl)-phenylammonium bromide, di-3-(methox butanoate, calcium 3-(propylcarbonyloxy)-propanoate, ycarbonyl)-propyldiethylphosphonium iodide, di-4- magnesium 2-(methylcarbonyloxymethyl)-acetate, ber (ethylcarbonyloxy)-butyl-dimethyl ammonium chlo yllium 4-(ethoxy-carbonylmethyl)-butanoate, cesium 50 ride, tetra-5-(ethoxycarbonylmethyl)pentylphos 4-(ethoxymethyl)-benzoate, sodium 3-(propoxy)-naph phonium bromide, tetra-4-hydroxybutylammonium ac thoate, potassium 4-(ethoxy carbonyl)-benzoate, barium etate, tetra-3-chloropropylphosphonium acetate, tetra 2-(hydroxy)-acetate, rubidium 2-chloropropanoate, methylammonium thiocyanate, tetraethylphosphonium magnesium 4-bromobenzoate, magnesium phenolate, selenocyanate, tetra-(4-methylphenyl)ammonium chlo and mixtures thereof. 55 ride, tetra-(3-phenyl-1-propyl)phosphonium bromide. Preferred Group 3 Co-catalysts III include the Na, K, Preferred Group 5 Co-catalysts III include the unsub Rb and Cs acetates. stituted tetra lower alkyl (e.g., C1 to C5 alkyl) ammo Suitable alkali and alkaline earth metal pseudohalide nium hydroxides, bromides, iodides, chlorides, fluo Co-catalysts III (referred to herein as Group 4 Co rides, and acetates. catalysts III) include those which possess pseudohalide 60 Suitable hydrogen halides (referred to herein as anions selected from the group consisting of SCNT, Group 6 Co-catalysts III) include HF, HCL, HBr, and SeCN, TeCN, OCN, and CNO, and mixtures HI. thereof. Preferred Group 6 Co-catalysts III include HI, HBr, Illustrative examples of such Group 4 Co-catalysts III and HCl, include NaSCN, NaSeCN, KSeCN, CSSeCN, Na 65 Suitable halogenated hydrocarbons (referred to TeCN, KTecN, NaOCN, NaCNO, KOCN, KCNO, herein as Group 7 Co-catalysts III) are described in CSOCN, CsCNO, CsTeCN, Mg(SeCN)2, Ca(TeCN)2, commonly assigned U.S. patent application Ser. No. Ca(OCN)2, Ca(CNO)2 and mixtures thereof. 399,270, filed July 19, 1982, by R. Austin and R. Micha 4,496,778 25 26 elson, the disclosure of which is herein incorporated by Specific Group 8 metal halides include AlCl3, GaBr3, reference including any halogenated hydrocarbon com T1Cl3, SiCl4, SiBra, PI3, PBr3, SbF5, Sbbr3, SbI3, BiCl3, pound, preferably a halogenated hydrocarbon com BiBr3, Asls, AsBr3, AsCl3, SeF4, SeCl4, SeBrA, TeF4 pound, wherein the hydrocarbyl portion is selected and mixtures thereof. from saturated aliphatic, saturated alicyclic, and aro Suitable halogen Co-catalysts III (referred to herein matic. as Group 9 Co-catalysts III) include F2, Cl2, Br2, and I2. More specifically, suitable Group 7 Co-catalysts III Any of the Co-catalysts III described in each of the can be represented by the structural formula: aforenoted Group 1 to 9 Co-catalysts III can be em ployed alone or in conjunction with one or more Co (Rs-X), (XV) O catalysts III in the same group and/or with one or more of the Co-catalysts III in the remainder of said groups in wherein R3 can be inertly substituted or unsubstituted: any amounts effective to increase the rate and/or selec alkyl, typically alkyl of from about 1 to about 20, prefer tivity of the hydroxylation reaction relative to that ably from about 1 to about 10, most preferably from observed in their absence. about 1 to about 5 carbons, aryl, typically aryl of from 15 Accordingly, while any effective amount of Co about 6 to about 14, preferably 6 to about 10, most catalyst III can be employed, it is contemplated that preferably 6 carbons, aralkyl and alkaryl wherein the such effective amounts constitute typically from about alkyl and aryl groups thereof are as defined immediately 0.1 to about 10,000 mole percent, preferably from about above, cycloalkyl, typically cycloalkyl of from about 4 10 to about 1000 mole percent, and most preferably to about 20, preferably from about 5 to about 15, and 20 from about 25 to about 75 mole percent, Co-catalyst III, most preferably from about 5 to about 10 carbon atoms; based on the total number of moles of osmium in the X is at least one halogen independently selected from osmium catalyst employed. the group consisting of F, Cl, Br, and I, and preferably When a supported osmium catalyst is employed, it Brand/or I; n' is a number of from about 1 to about 10, typically will be utilized as a fixed bed through which preferably from about 1 to about 8 (e.g., 2 to 6), and 25 the reaction mixture containing the Co-catalyst I, II, most preferably from about 1 to about 6 (e.g., 2 to 4); and III preferably are determined in a supported system and said R1s substituents including hydroxy, ether and based on the volume of reaction mixture in contact with ester groups, said ether and ester substituents, being as the fixed bed of supported osmium at any given time described in connection with R"12 of structural formula during the hydroxylation reaction (referred to herein as (XII). The term “inertly substituted” is defined herein 30 the "effective volume”), e.g., the aforedescribed mole to mean any organic or inorganic substituent which is percents and/or ratio are contained in the effective stable under reaction conditions and does not adversely volume of the reaction mixture. affect the performance of said co-catalyst, relative to Illustrative examples of suitable Co-catalyst combina the unsubstituted halogenated organic compound. tions include CuBr2 and pyridine; Cu(NO3)2, pyridine Representative examples of suitable Group 7 Co 35 and NaBr; CuCl2, pyridine, and NaBr; CuBr2, pyridine, catalysts III include iodomethane, bromomethane, NaBr; copper acetate, pyridine, and tetraethyl ammo iodoethane, bromoethane, 1,2-dibromoethane, chloro nium chloride; Cul2, pyridine, and KBr; Cu(NO3)2, ethane, 1,2-dichloroethane, 1-iodopropane, 1-bromo pyridine, and CsBr; CuI, pyridine, and NaBr; and Cu(- propane, 1-chloropropane, 2-iodo-1-methylethane, 2 NO3)2, pyridine, and n-butyl bromide. bromo-1-methylethane, 2-chloro-1-methylethane, 1 40 In the aforedescribed catalyst composition compris iodobutane, 2-iodobutane, 2-bromobutane, 1-chlorobu ing at least three components, namely, a catalytically tane, 2-methyl-2-iodopropane, 2-methyl-2-bromopro active osmium compound, Co-catalyst I and Co pane, 1-iodo-1-methylpropane, 1-bromo-1-methylpro catalyst II, the third component, i.e., Co-catalyst II, pane, 1-chloro-1-methylpropane, i-iodo-1,1-dimethyle 45 unexpectedly substantially improves the rate of reaction thane, 1-chloro-1,1-dimethylethane, 1-chloro-1,1-dime for hydroxylating olefins with molecular oxygen rela thylethane, benzyliodide, phenyliodomethane, phenyl tive to its absence. Although the exact mechanism and reason for this effect is not fully understood, it is consid chloromethane, phenylbronomethane, 1,2-dichloro ered that the results speak positively for themselves. benzene, 2-bromoethanol, 2-chloroethanol, 2-iodoe However, the following is offered as an explanation of thanol, 1-phenyl-2-iodoethane, 1-phenyl-4,4- 50 dichlorobutane, 1-(1,2-dichloroethyl)-benzene, the mechanism for the observed catalytic effect in con nection with the use of osmium tetroxide as the catalyti chloropropyl)-naphthylene and mixtures thereof. cally active osmium compound, although such explana Preferred Group 7 Co-catalysts include iodomethane, tion is not intended to be exhaustive of all possible bronoethane, 1-bromobutane, 1-iodobutane, 1-bromo mechanistic details. It is known that osmium tetroxide 1,1-dimethylethane, i-iodo-1,1-dimethylethane, 2 55 iodobutane, 2-bromobutane, 2-methyl-2-iodopropane, adds across the olefin double bond of the compound to 2-methyl-2-bromopropane, 2-bromoethanol, 2-chloroe be hydroxylated to yield an intermediate cis-ester as thanol, 2-iodoethanol, and mixtures thereof. follows: The most preferred Group 7 Co-catalysts III contains bromide and includes 1-bromobutane, bromomethane, 60 2-bromobutane, 2-methyl-2-bromopropane, 2-bromoe NHc=CH / + OsO4 -G al C C 1 thanol, and mixtures thereof. H1 NH Representative examples of suitable Group III-b, So IV-b, V-B, and VI-b metal halides (according to the o1 NoS. periodic chart of Cotton and Wilkinson "Advanced 65 Inorganic Chemistry" (3rd ed. 1972)) referred to herein The osmium complex is now formally in the +6 as Group 8 Co-catalysts III include halides of Al, Ga, oxidation state. The glycol product can be obtained In, Tl, Ge, Sn, Pb, P, Si, As, Sb, Bi, S, Se, Te, and Po. from this complex by a reductive procedure which is 4,496,778 27 28 commonly used in the well-known stoichiometric pro valence of copper of Co-catalyst I as initially employed cedure wherein the osmium compound acts as the oxi be that which represents the highest stable oxidation dant, or it can be obtained by oxidative hydrolysis in the state thereof, since such metals must be capable of being presence of an oxidant. This latter route is believed to reduced upon oxidizing the Os-8. While this is not be operating in the present invention. critical, it avoids the need in some instances to initially Considering this system, it is believed that the copper oxidize the transition metal in-situ so that it can be re of Co-catalyst I serves to mediate the reoxidation of duced. osmium by oxygen with concurrent hydrolysis of the While the hydroxylation reaction can be conducted glycolate, the copper itself being reduced in the process. in a heterogeneous multiphase system, the preferred The Co-catalyst II, e.g. pyridine, is believed in turn to 10 mode for conducting the hydroxylation reaction is in a mediate the reoxidation of the copper through some liquid reaction mixture, preferably provided as a homo from of complexed intermediate thereof and/or en geneous or substantially homogeneous medium by using hance the solubility of Co-catalyst I in the reaction an inert organic solvent to dissolve, where possible, medium and/or assist in the oxidative hydrolysis of the whatever components are employed in the catalyst and osmium glycolate. Furthermore, the presence of a halo 15 co-catalyst system and reactants. Partial immiscibility of moiety in the reaction mixture is believed to facilitate the solvent with water is acceptable although not pre rate of hydrolysis of the glycolate intermediate and may ferred. By an inert solvent is meant one which does not also help to mediate the reoxidation of the transition undergo oxidation during the course of the reaction. metal. More specifically, by "halo-" is meant to include Suitable inert organic solvents include aliphatic or halogen in the form of organic and inorganic halide salts aromatic alcohols having from 1 to about 10 carbon or complexes, halogenated hydrocabons, hydrogen atoms, preferably tertiary alcohols, aliphatic or aro halides as well as the free halogens themselves. Accord matic ketones having from 3 to about 10 carbon atoms, ingly, it is preferred to provide a halo-source in the aliphatic or alicyclic ethers having from 2 to about 10 reaction mixture. This is typically achieved through the carbon atoms, glycols having from 2 to about 10 carbon use of a copper halide as Co-catalyst I. If, however, 25 atoms, N, N-dialkyl amides having from 3 to about 10 Co-catalyst I is not employed as a halide salt, it is pre carbon atoms, nitriles having from about 2 to about 10 ferred to introduce a halo-source through an alternative carbons, aliphatic or aromatic sulfoxides having from 2 means. This can easily be achieved through the appro to about 14 carbon atoms, aliphatic or aromatic sulfones priate selection of any halo-containing Co-catalyst III, having from 2 to about 14 carbon atoms, and the like. such as for example those described hereinabove includ 30 Examples of suitable solvents include methanol, etha ing alkali or alkaline earth metal halides (e.g. Group I nol, propanol, butanol, hexanol, decanol, t-butyl alco Co-catalyst III), tetrahydrocarbyl ammonium or phos hol, t-amyl alcohol, benzyl alcohol, acetone, methyl phonium halides (e.g., Group 5 Co-catalysts III), hydro ethyl ketone, methylbutyl ketone, acetophenone, ethyl gen halides (e.g. Group 6 Co-catalysts III), halogenated ene glycol, propylene glycol, diethylene glycol, tetra hydrocarbons (e.g. Group 7 Co-catalysts III), metal 35 ethylene glycol, dimethyl formamide, diethyl form halides (e.g. Group 8 Co-catalysts III) and halogens amide, dimethyl acetamide, dimethyl sulfoxide, diethyl (Group 9 Co-catalysts III), as well as transition metal sulfoxide, N,N-butyl sulfoxide, diphenyl sulfoxide, di halides. The halo-source can also be any of the osmium benzylsulfoxide, dimethyl sulfone, diethyl sulfone, tet halides described in connection with the suitable os ramethylene sulfone (sulfolane), diphenyl sulfone, ace mium containing compounds. For economic reasons it 40 tonitrile, dioxane, tetrahydrofuran, tetrahydropyran, may be more desirable to employ an inexpensive halo dioxolane, adiponitrile and mixtures thereof. source such as NaBr to fulfill the aforedescribed halo The preferred solvents include those which are sub gen balance rather than use the more expensive osmium stantially or completely miscible with water such as halides or transition metal halides for this purpose. t-butyl alcohol, methanol, as well as glycols and/or Thus, for optimum performance of the reaction sys 45 polyols derived from the olefin being hydroxylated. tem, it is preferred to establish a balance, in terms of The most preferred solvents are dipolar and aprotic amounts, between osmium in the osmium catalyst, the such as sulfolane, acetonitrile, N,N-dimethyl acetamide, copper of Co-catalyst I, and halogen in the halo-source N,N-dimethylformamide, adiponitrile, and dimethyl present in the reaction mixture. Accordingly, it is con sulfone. templated that the mole ratio of Os:copper:halogen in 50 The inert solvent is preferably employed in amounts the halo-source, in contact with the olefin to be hydrox sufficient to achieve a homogeneous solution with re ylated be controlled to be typically from about 1:1:1 to spect to at least the olefin and catalyst and Co-catalyst about 1:100: 1000, preferably from about 1:10:100 to system. Typically such amounts can vary from about 0 about 1:50:500, and most preferably from about 1:15:20 to about 98%, (e.g., 10 to 90%), preferably from about to about 1:40:200. In satisfying this balance any halogen 55 about 10 to about 90%, and most preferably from about in the halo-source, e.g. the osmium catalyst, or Co 20 to about 80%, by weight, based on the total weight catalysts is taken into consideration. of the reaction mixture. While the above discussed mechanism relates specifi Water is provided to, and/or is present in, the initial cally to the use of OsO4 as the osmium catalyst, the reaction mixture in at least a stoichiometric molar ratio other osmium containing compounds discussed above 60 with the molar amount of ethylenic unsaturation to be will also form cis-ester intermediates which must be hydroxylated in the olefin. Such ratios preferably are hydrolyzed, although these intermediates are not of the also present in the reaction mixture at any given time same chemical composition. Thus, the Co-catalysts I after start-up. Accordingly, water is provided in the and II as well as the halo-source are believed to function reaction mixture at molar ratios, of water to ethylenic through similar mechanisms regardless of the form of 65 unsaturation to be hydroxylated in the olefin of from the osmium compound employed. about 1:1 to about 100:1, preferably from about 1:1 to Furthermore, in view of the above discussion, it is about 10:1, and most preferably from about 1:1 to about recommended for best results that the most preferred 2:1. Such molar ratios typically can be achieved by 4,496,778 29 30 controlling the amount of water in the reaction mixture necessarily be very low if based on the component pres to be from about 2 to about 90%, preferably from about ent in large excess. This is not a problem in a continuous 5 to about 50%, and most preferably from about 10 to process since unreacted components are recycled. about 30%, by weight, based on the total weight of the The hydroxylation reaction is typically conducted at reaction mixture. Preferably the amount of water em- 5 temperatures of from about 40” to about 250° C., prefer ployed is less than that which will cause separation of ably from about 60° to 200° C., and most preferably the reaction mixture into an aqueous phase and organic from about 80° to about 170° C. to achieve high selec phase. tivities for the hydroxylated olefin. The amount of water employed within the aforedes At temperatures greater than the aforenoted ranges, cribed ranges is also influenced by the amount of O2 in 10 the reaction rate increases subtantially but this usually the system. Thus, the mole ratio of H2O to O2 dissolved occurs at the expense of a reduction in selectivity. At in the reaction mixture is typically controlled to be from very low reaction temperatures, e.g., below about 0°C., about 1:1 to about 30:1, preferably from about 1:1 to the reaction rate decreases to a commercially undesir about 15:1, and most preferably from about 1:1 to about able degree. Accordingly, while the reaction tempera 6:1. 15 ture is not critical and can vary over a wide range, one The pH of the reaction mixture during the hydroxyl normally would not operate at temperature extremes ation reaction need not be rigidly controlled although it outside the aforenoted ranges. Furthermore, since it is will preferably not be allowed to drop below about 4, preferred to conduct the hydroxylation reaction in the preferably not below about 6. Likewise, the pH of the liquid phase, the reaction temperature is typically se reaction mixture preferably will not be allowed to ex- 20 lected in conjunction with the reaction pressure to ceed about 12 although the process can still be con achieve this goal. ducted at a pH below 4 and above about 12. Active pH For the production of ethylene glycol, propylene control is generally not needed since the pH of the glycolor any glycol derived from any unsaturated gase reaction mixture will typically autogeneously vary be ous olefin, the latter may be bubbled through the reac tween about 4 and 12, preferably between about 5 and 25 tion mixture containing the components described 12, and most preferably between about 5 and 7. herein or it may be introduced under pressure. Likewise Furthermore, it will be understood that the use of with the oxygen containing gas. However, it is pre oxygen in accordance with the process of the present ferred that the reaction takes place in the liquid phase. invention inherently avoids the peracid route of olefin Consequently, sufficient pressure is preferably em hydroxylation, and assures the direct hydroxylation of 30 ployed to maintain the gaseous reactants (i.e., olefin and the olefin. It is also preferred to conduct the hydroxyl oxygen) in the liquid phase and/or to dissolve the gase ation reaction in the absence of any organic carboxylic ous reactants into the liquid reaction mixture. acid such as acetic or propionic acid to avoid esterifica Although the magnitude of the pressure is not criti tion of the diol product. cal, it determines the amount of the gaseous reactants The primary oxidant employed in the present inven- 35 that are present in the reaction mixture and therefore tion is molecular oxygen. Such oxygen can be added as affects the rate of reaction. Accordingly, the total pres a pure oxygen or as part of an oxygen containing gas sure of the gases in contact with the reaction mixture is Such as air or some other oxygen containing gas having typically controlled to be from about 200 to about 2000 one or more inert compounds such as CO2 or N2 present psig, preferably from about 300 to about 1500 psig, and therein. Generally, the oxygen containing gas is present 40 most preferably from about 300 to about 700 psig at the within, preferably dissolved in, the reaction mixture in aforenoted reaction temperatures. The partial pressure amounts sufficient to achieve hydroxylation of the ole of each reactant gas, i.e., olefin and oxygen, can be fin. controlled to achieve the aforenoted molar ratios. Accordingly, the molar ratio of oxygen to olefin When the reactant olefin gas is ethylene, the partial ethylenic unsaturation can vary widely but for safety 45 pressure (at reaction temperatures) thereof is typically reasons it is preferably maintained outside explosive controlled to be from about 100 to about 2000 psig, limits. preferably from about 200 to about 1500 psig, and most For example, when hydroxylating ethylene or propy preferably from about 300 to about 1200 psig; while lene, if oxygen is in excess of stoichiometry, the ratio when propylene is the reactant olefin, the partial pres typically will be 98 weight % oxygen or more and 2% 50 sure (at reaction temperatures) thereof is typically con or less of the olefin. Preferably, however, the olefin is trolled to be from about 100 to about 2000 psig, prefera employed in excess, preferably large excess, of stoichi bly from about 200 to about 1500 psig, and most prefera ometry, and the oxygen concentration of the oxidizing bly from about 300 to about 1000 psig gas typically will be about 10 mole % oxygen and about When the olefin reactant is a liquid or is dissolved in 90 mole % olefin. When oxygen is in excess of stoichi- 55 the reaction mixture under pressure, its concentration in ometry, olefin can be added as the reaction proceeds. the reaction mixture typically will vary from about 1 to On the other hand, where the olefin is in excess of stoi about 90%, preferably from about 20 to about 80%, and chiometry, oxygen can be added during the reaction as most preferably from about 20 to about 60%, by weight, the oxygen is consumed. based on the total weight of the reactant mixture. Accordingly, in view of the above, the oxygen con- 60 In carrying out the invention, olefin, water, oxidant, taining gas preferably is dissolved in the reaction mix osmium catalyst, co-catalysts, and optional inert solvent ture in an amount sufficient to achieve a molar ratio of are brought into contact in a manner and under condi ethylenic unsaturation to be hydroxylated in the olefin tions sufficient to hydroxylate the olefin, i.e., to directly to oxygen in excess of 1:1, typically up to as high as convert at least one of the ethylenic unsaturations pos 100:1; and outside the explosive limits of the reaction 65 sessed thereby to its corresponding diol. mixture. It is to be noted, that when either olefin or O2 Accordingly, the hydroxylation reaction can be per is employed in Substantial excess of stoichiometry for formed as a batch reaction, as a continuous reaction or safety reasons the conversion in a batch process will as a semi-continuous reaction. In the batch reaction, the 4,496,778 31 32 osmium catalyst is charged into the reaction vessel as a Unless otherwise specified, in the following exam solution in the inert solvent along with the Co-catalyst ples, selectivity, yield, and conversion are calculated as I, Co-catalyst II, optional Co-catalyst III, water, and follows: olefin if in liquid form. The reaction vessel is then pres 5 surized with oxygen and olefin if in gaseous form. It Moles of glycol formed may be desirable to heat the liquid reaction mixture to % Selectivity as Moles of oxygenated product formed X 100 reaction temperature prior to pressurizing with the reactant gases. The reaction is allowed to proceed to the an - Moles of oxygenated product formed desired degree of completion. % Conversion = Moles of olefin charged X OO O In the continuous process, the components can be % Yield = % Conversion i. Selectivity introduced into the inlet of an elongated reactor at a rate such that substantially complete reaction will have taken place by the time the reaction mixture reaches the The following Comparative Example and Examples reactor outlet. The reaction can be carried out in a 1 to 9 are provided to illustrate not only the effect of semi-continuous manner by metering the reactant mix 15 pyridine (Co-catalyst II) on the reaction rate, but also ture components into a series of two or more tank reac the effect of varying the amount of pyridine in relation tors at the appropriate rate to maintain the reactor liq to Co-catalyst I. The rate enhancement is illustrated by uid level. conducting several experiments for the same reaction Additionally, the process may be run in either of the time and observing the amount of glycol product pro aforementioned modes by altering the reaction condi duced as a function of the amount of pyridine em tions, and/or, the reactant, solvent, catalyst, and co ployed. catalysts concentrations during the course of the reac tion. Thus, the process may be run by changing the COMPARATIVE EXAMPLE temperature, pressure, catalyst concentration, oxidant 25 The following Comparative Example omits pyridine concentration, and/or olefin concentration. therefrom and is intended to act as a blank against The spent reaction mixture after removal of unre which the following examples can be compared. acted olefin is a solution of product glycol, by-products Two solutions were prepared as follows: A 30 ml if any, solvent, water, and catalyst system components. mixture of 80% (V/V) sulfolane and 20% (V/V) water The volatile components are distilled out of the reaction was prepared and 0.19 mmoles of OsO4 were dissolved mixture into various fractions leaving non-volatile cata lyst system components in the still. The product glycol therein to form Solution 1. To a 50 ml sulfolane/water is then separated from the high boiling distillate. (4:1 V/V) mixture was added and dissolved 5 mmoles of If the hydroxylation reaction is to be conducted using CuBr2 to form Solution 2. Solution 1 was then added to the supported osmium catalyst, this is typically 35 a stirred 300 cc autoclave, equipped with a gas dispers achieved in fixed bed or slurry form. In the fixed bed ing jet followed by Solution 2 with stirring. Thirty mode, the liquid reaction mixture, preferably a homoge grams of propylene were then charged to the reactor. neous reaction mixture, is prepared comprising oxidant, The stirred solution was then heated to 110° C. and 50 co-catalysts, water and olefin and the reaction mixture mmoles of molecular oxygen charged thereto. A total is passed, preferably continuously, through a fixed bed 40 pressure of 870 psig was recorded. The reaction was reactor containing the supported catalyst at reaction allowed to proceed for 20 minutes measured from com temperature and at a rate such that substantially com pletion of the O2 addition during which time a 20 psig plete reaction will have taken place by the time the pressure drop was observed. The mixture was then reaction mixture reaches the reactor outlet. A variety of quickly cooled and the pressure released. A brown, fixed bed reactors will be found to be useful and multi 45 turbid solution (pH 3.5) was obtained from the reactor ple tube heat exchanger type of reactors are satisfac and analyzed by gas chromatography (5% SP-100 on tory. In the slurry mode, a reaction mixture containing Supelcoport) and showed the production of 16 mmoles the above-described components and suspended sup of propylene glycol. This corresponds to a 16% yield of ported osmium catalyst is charged into a reactor vessel propylene glycol based on oxygen charged. Minor along with olefin and the reaction is allowed to proceed 50 amounts of acetone 1,2-dibromopropane, and bromo to completion. In a continuous slurry mode, the reac propanol were also produced. The results are summa tion mixture components can be introduced into the rized at Table 2, Run 1. inlet of an elongated reactor adapted to retain, e.g., by filtration, the slurried supported catalyst at a rate such EXAMPLES TO 9 that substantially complete reaction will have taken 55 Comparative Example 1 was repeated 9 times in 9 place by the time the reaction mixture reaches the reac separate experiments with the exception that pyridine tor outlet. The slurry mode can also be carried out in a was added, in successively higher amounts for each Semi-continuous manner by metering the reactant mix experiment, to Solution 1 prior to introduction into the ture components into a series of two or more tank reac 60 reactor as shown at Table 2, Runs 2 to 9. The results are tors adapted as described above at the appropriate rate also summarized at Table 2. to maintain the reactor liquid level. The following examples are given as specific illustra COMPARATIVE EXAMPLE 2 tions of the claimed invention. It should be understood, Comparative Example 1 was repeated with the ex however, that the invention is not limited to the specific 65 ception that the sulfolane solvent was omitted from details set forth in the examples. All parts and percent Solutions 1 and 2 and replaced with pyridine. Thus, ages in the examples as well as in the remainder of the pyridine is the sole solvent. The results are summarized specification are by weight unless otherwise specified. at Table 2, Run 10. 4,496,778 33 34 EXAMPLES 9-17 EXAMPLE 20 The following Examples 9-17 are provided to illus Into a 300 ml titanium autoclave was charged 1 g of trate the performance of various pyridine and imidazole 1% Os metal on silica (0.05 mmole Os) as a slurry in 15 derivatives. 5 g sulfolane, CuBr2 (5 mmole) dissolved in 61 g of sulfo Thus, the procedures of Example 3 were repeated lane, pyridine (13 mmole) and water (19 g). Propylene using 12.4 mmoles of a different Co-catalyst II for each (30 g) was added to the autoclave and the contents of Examples 9-17 to hydroxylate propylene. The results warmed to 110° C. Oxygen (60 psig) was added and the as well as the identity of each Co-catalyst II are summa mixture stirred at 110° C. for 1.5 hours. Propylene gly rized in Table 3, Runs 11-19. 10 col (7.1 mmole) was produced with a selectivity of about 86%. The conversion based on propylene was COMPARATIVE EXAMPLES 3 TO 12 1.0%. In accordance with the procedure of Example 3, 12.4 mmoles of a different aromatic amine, imidazole, or COMPARATIVE EXAMPLE 15 aliphatic tertiary amine, outside the scope of the Co 15 Example 20 was repeated with the exception that catalyst II of the present invention, for each of Compar pyridine was omitted from the reaction mixture. Prod ative Examples 3 to 12, was employed in the hydroxyl uct analysis, after 1.5 hours of reaction time, showed 1.4 ation of propylene. The results as well as the identity of mmole of propylene glycol, a selectivity to propylene each amine employed is summarized at Table 4, Runs 20 glycol of 50%, and a conversion based on propylene of 20-29. <1.0%. EXAMPLE 18 EXAMPLE 2. The following example illustrates the use of an os The following runs illustrate the use of pyridine, a mium halide as the osmium catalyst. 25 non-halide containing copper salt in conjunction with Into a 300 ml titanium autoclave was charged OsBr3 OsO4 (Run A) or OsBr3 (Run B), and a halide contain (0.085 g, 0.20 mmole) in 30 ml of sulfolane/H2O (4:1 ing Co-catalyst III. V/V), CuBr2 (1.34 g, 6.0 mmole) in 50 ml sul RUN A folane/H2O (4:1 V/V), and (13 mmole of pyridine). Propylene (37.0 g) was added to the autoclave and the 30 Into a 300 ml titanium autoclave was charged OsO4 contents warmed to 90° C. Oxygen was added (60 psig (0.2 mmole) in 20 g of sulfolane/H2O (4:1 w/w), Cu(- from a 300 cc addition vessel) and the mixture stirred NO3)2.3H2O (1.21 g, 5.0 mmole), pyridine (13 mmole), for 1.5 hours upon completion of the oxygen addition. and NaBr (10 mmole) in 75.0 g sulfolane/H2O (4:1 The product solution was analyzed by gas chromatog w/w). Propylene (30 g) and O2 (60 psig) were intro raphy which indicated the production of 53 mmole PG. 35 duced as in all previous examples and the reaction mix The selectivity was about 98% and the conversion ture was stirred for one hour. Propylene glycol (80 based on propylene was 6%. The pH at the end of the mmole) was produced at better than 99% selectivity. run was about 4.5. The conversion based on propylene was 11.2%. RUN B COMPARATIVE EXAMPLE 13 40 Example 18 was repeated with the exception that Run A was repeated with the exception that Osbr3 pyridine was omitted from the reaction mixture. After (0.086 g, 0.2 mmole) was used as the osmium source. 1.5 hours of reaction time product analysis showed 23.4 Product analysis, after one hour of reaction time, mmoles of propylene glycol. The selectivity to propy showed 52 mmole of propylene glycol, a selectivity to 45 propylene glycol of 99%, and a conversion based on lene glycol was 85% and the conversion based on prop propylene of 7.2%. ylene was 3.3%. The difference in conversions between Runs A and B EXAMPLE 1.9 is attributable to the fact that Osbris requires an induc tion period during which it is believed that osmium is Into a 300 ml titanium autoclave was charged Os3 50 oxidized to a higher oxidation state before it exerts its (CO)12 (0.045 g, 0.05 mmole) in 50 g of N,N-dimethyl catalytic effect. Consequently, given a longer reaction formamide (DMF), CuBr2 (1.12g, 5.0 mmole) dissolved time, the conversion of Run B would be similar to Run in 26 g DMF, 19.0 g of H2O, and pyridine (13 mmole). A. Propylene (30 g) was added to the autoclave and the contents warmed to 110° C. Oxygen was added (60 psig 55 COMPARATIVE EXAMPLE 16 from a 300 cc addition vessel) and the mixture stirred at Example 21 was repeated with the exception that 110° C. for one hour upon completion of the oxygen pyridine was omitted from the reaction mixture. Prod addition. Propylene glycol (18 mmole) was produced at uct analysis, after 1 hour of reaction time showed 35 a selectivity of 99%. The conversion based on propy mmoles (Run A) and 24 mmoles (Run B) of propylene lene was 2.5%. 60 glycol, a selectivity to propylene glycol of 98% (Run COMPARATIVE EXAMPLE 14 A) and 96% (Run B), and a conversion based on propy lene of 4.9% (Run A) and 3.4% (Run B). Example 19 was repeated with the exception that pyridine was omitted from the reaction mixture. Prod EXAMPLE 22 uct analysis after 1 hour of reaction time showed 11 65 The following example illustrates the use with pyri mmoles of propylene glycol, a selectivity to propylene dine of a non-halide containing copper salt co-catalyst, glycol of 98%, and a conversion based on propylene of OsO4 (Run A"), or OsBr3 (Run B') in the absence of a 1.5%. halide containing Co-catalyst III. 4,496,778 35 36 RUN A' EXAMPLE 23 Example 21 (Run A) was repeated in the absence of This example illustrates the use of higher amounts of NaBr. Product analysis, after one hour of reaction time, oxygen than the previous examples, thereby relieving showed 20 mmoles of propylene glycol, a selectivity to 5 the limitations on conversion imposed by using excess propylene glycol of greater than 99%, and a conversion propylene and calculating the conversion based on based on propylene of 2.8%. propylene. To 20 ml of a mixture of 65 volume % N,N-di RUN B' methylformamide (DMF) and 35 volume 2% water was Example 21 (Run B) was repeated in the absence of 10 added 0.19 mmoles of OsO4 and 12.4 mmoles of pyri NaBr. Product analysis, after one hour of reaction time, dine. To 36 ml of a second solution of 65 volume 2% showed 13.4 mmole of propylene glycol, a selectivity to DMF and 35 volume 2% water was added 5.0 minoles of propylene glycol of greater than 99%, and conversion CuBr2. These solutions were added successively to a based on propylene of 1.9%. 300 cc stirred autoclave equipped with a gas dispersing 15 jet, followed by 30 g of propylene. The mixture was COMPARATIVE EXAMPLE 17 heated to 140 C. with stirring. At 140° C. oxygen was Example 22 was repeated with the exception that added in decreasing increments every five minutes for a pyridine was omitted from the reaction mixture. Prod period of one hour. The oxygen level was thus main uct analysis, after 1 hour of reaction time, showed 7.4 tained close to, but not exceeding, the upper-explosive mmoles (Run A") and 3.3 mmoles (Run B') of propylene 20 limits of the propylene-oxygen mixture. After one hour, glycol, a selectivity to propylene glycol of 88% (Run oxygen was added at six minute intervals for 42 more A"), and 95% (Run B), and a conversion based on prop minutes. At this point no more oxygen was added and ylene of 1.1% (Run A") and 0.5% (Run B'). the reaction was allowed to continue for 18 more min COMPARATIVE EXAMPLE 1.8 utes followed by rapid cooling. A pressure drop of 450 25 psig was recorded throughout the course of the reac Example 18 was repeated with the exception that the tion. A total of about 260 mmoles of O2 was added, and Co-catalyst I (the copper salt) was omitted from the analysis by gas chromatography showed that 496 reaction mixture. Product analysis after 1 hour reaction mmoles of propylene glycol were produced. Selectivity time, showed 0 mmoles of propylene glycol, a selectiv to propylene glycol was 98.7% with a conversion based ity to propylene glycol of 0%, and a conversion based 30 on propylene of 70.4%. The yield of propylene glycol on propylene of 0%. was 69.5%. TABLE 2 P.G. Ex. Comp.Of Pyri- Pyr/Cu DropPressure ofpH Reac. / \ P.G. Run. Ex. dine Mole Observed Product Time Conv. Yield No. No. 1 (mmoles) Ratio (psig) Sol. (min.) mnoles Sel. (%) 7% (%) 1 Comp. O O 20 3.5 20 16 75 3.0 2.23 Ex.1 2 1 2.5 O.S 5 3.8 20 19.5 83 3.3 2.73 3 2 5.0 1.0 25 4.0 2O 31.0 1OO 4.3 4.3 4 3 12.4 2.5 55 5.1 2O 59.0 OO 8.3 8.3 5 4. 19.0 3.75 75 5.3 2O 6.0 100 8.5 8.5 6 5 25.2 5.0 90 5.5 20 69.0 OO 9.7 9.7 7 6 30.2 6.0 70 5.5 20 57.5 100 8.1 8. 8 7 35.3 7.0 60 5.6 20 48.0 100 6.7 6.7 9 8 50.4 10.0 60 5.7 20 450 100 6.3 6.3 10* Comp. 990 200 5 6.5 20 14.7 OO 2.1 2.1 Ex. 2 P.G. = propylene glycol product Pyr = pyridine "This run illustrates use of Pyridine as a solvent

TABLE 3 Co. Cat.II P.G. Run. Ex. / \ pHProduct of TimeReaction / \ Conv. YieldP.G. No. No. Type mmoles Sol.(--) (min.) mmoles Sol. (%) (%) (%) 9 2,4-DMP 12.4 5 20 53.0 OO 7.4 7.4 12 O 3,5-DMP 12.4 5 2O 6.3.3 OO 8.9 8.9 3 11 2-MP 12.4 5 2O 39.2 1OO 5.5 5.5 14 12 4-MP 12.4 5 20 59.0 1OO 8.3 3.3 15 13 4-PP 12.4 5 2O 54.5 OO 7.6 7.6 6 14 2,6-DMP 12.4 s 2O 2O,O OO 2.8 2.8 17 15 1,2-DAB 12.4 5 2O 20.0 OO 2,8 2.8 18 16 l-MIm 2.4 S.O 2O 56.5 OO 7.9 7.9 4,496,778 37 38 TABLE 3-continued Co. Cat. II P.G. pH of Reaction P.G. Run. Ex. Product Time Conv. Yield No. No. Type mmoles Sol. (-) (min.) mmoles Sol. (%) (%) (%) 19 17 2-DMIn 12.4 3.5 2O 65.0 100 9. 9.1 DAB = diazabenzene DMP = dimethyl pyridine MP = methyl pyridine PP = phenyl pyridine P.G. = propylene glycol product Min = methylimidazole DMIm = dimethylimidazole

TABLE 4 Co. Cat. II P.G. Comp. pH of Reaction P.G. Run. Ex. Product Time Conv. Yield No. No. Type Immoles Sol. (min.) mmoles Sol. (%) (%) (%) 2O 3 TEA 12.4 7.5 2O 9.4 100 .3 1.3 21 4 QNL 12.4 8.6 2O 9.7 100 .4 1.4 22 5 2,2'-BIP 12.4 5.5 20 O O O 0. 23 6 1,4-DAB 12.4 4.0 20 1 O O O 24 7 BI 2.4 - 5.0 20 6 70 1.2 0.8 25 8 1,3-DAB 2.4 4.5 20 6 100 0.8 0.8 26 9 TMED 12.4 5.9 20 O O O O 27 10 Im 12.4 5.2 20 15.5 100 2.2 2.2 28 l 1,8-DAN 12.4 3.5 20 6.0 100 0.8 0.8 29 12 4,5-DAP 12.4 5.5 20 O O O 0 TEA = Triethylamine QNL = quinuclidine (l-azabicyclo[2.2.2]octane) BIP = bipyridine DAB is diazabenzene Bl = benzimidazoline (1H-1,3-diazaindene) TMED = N,N,N',N'-tetramethylenediamine In = imidazole DAN = diazanaphthalene

COMPARATIVE EXAMPLE 19 with the reaction mixture components is one of rate 35 inhibition rather than acceleration. The following Comparative Example illustrates the uniqueness of the interaction of copper with pyridine in DISCUSSION OF RESULTS the process of the present invention by substituting a Referring to Table 2, it can be seen that pyridine can different transition metal salt, i.e., manganese acetate increase the rate of reaction by as much as 4 times the (i.e. Mn(OAc)2) for the copper salt. 40 rate in its absence. The degree of rate enhancement however is a function of the amount of pyridine em RUN A ployed in relation to the amount of Co-catalyst I em Accordingly, into a 300 ml titanium autoclave was ployed. This relationship is not linear, however, the rate charged OsBr3 (0.08 g, 0.4 mmole), Mn(OAc)24H2O enhancement increasing to a pyridine:Cu mole ratio of (1.22 g, 5.0 mmole), and (C2H5)4NOAc (1.31 g, 5.0 45 about 5:1 (Run 6) and then decreasing at higher pyridine minole) dissolved in 95.6 g of sulfolane:H2O 4:1 w/w levels until the use of pyridine as the principal solvent solution. Propylene (30 g) was then added and the con (Run 10) results in oxidation rates no better than in its tents warmed to 110° C. Oxygen (60 psig) was then absence and actually reduces the oxidation rate below added and the reaction mixture stirred for 2.0 hours that of the blank (Run 1). The reason for this occur from completion of the addition. The reaction mixture rence is not entirely understood, but it is evidence that was then analyzed for product and found to contain pyridine is not operating via the same mechanism as 30.0 mmole of propylene glycol. The selectivity to when employed as a promoter for stoichiometric oxida propylene glycol was 85.0% with a conversion based tions which do not employ a transition metal co on propylene of about 4.2%. The pH at the end of the catalyst. reaction was about 5.3. 55 Referring to Table 3, it can be seen that a variety of pyridine or imidazole derivatives are also effective rate RUN B promoters. The different degrees of rate enhancement A run identical to Run A above was carried out ex observed for the various pyridine derivatives is believed cept pyridine (1.03 g, 13.0 mmole) was added to the to be attributable, in part, to the ability of the nitrogen reaction mixture. The product solution was analyzed 60 of Co-catalyst II to complex with the transition metal of after two hours from completion of the O2 addition and Co-catalyst I. found to contain 5.3 mmoles of propylene glycol with a Thus, the di-substituted pyridine, 2,6-dimethyl pyri selectivity to the same of about 50%. This corresponds dine (Run 16), which has a relatively high degree of to a propylene conversion of about 1%. The pH at the steric hindrance about the nitrogen bonding site, was end of the reaction was about 5.3. 65 found to be a less effective promoter for propylene From the results of Runs A and B it can be seen that hydroxylation than 3,5-dimethylpyridine (Run 12) hav pyridine actually decreases the selectivity and conver ing no steric hindrance. Furthermore, the 3,5-dimethyl sion is conjunction with Mn and therefore its interaction pyridine actually exhibited a slightly higher degree of 4,496,778 39 40 rate enhancement than pyridine itself. Partially hin 1. A process for hydroxylating at least one olefinic dered 2,4-dimethylpyridine (Run 11) is intermediate in compound having at least one ethylenic unsaturation ability to promote hydroxylation. The effect of steric which comprises reacting said olefinic compound in the condiserations on rate enhancement is also illustrated by presence of oxygen, water and a catalyst composition, the mono substituted pyridine derivatives of 2- and 5 in a manner and under conditions sufficient to convert 4-methylpyridine, the latter showing enhancement catalytically at least one of said ethylenic unsaturation equivalent to that of pyridine (Run 14) and the former directly to its corresponding diol, said catalyst composi (Run 13) being partially hindered and only 66% as ef tion comprising: fective. The aromatic substituted pyridine 4-phenyl (a) at least one catalytically active osmium containing pyridine (Run 15) was also observed to be an effective O compound; promoter. In the imidazole derivative series, it can be (b) at least one transition metal containing Co-catalyst I seen that 1-methyl imidazole (Run 18) and 1,2-dime having an identity and in an amount effective to in thylimidiazole are effective rate enhancers, while imid crease at least one of the rate and selectivity of the azole itself (Run 27) has practically no effect. hydroxylation reaction relative to its absence, said In the diazabenzene series of promoters, it can be seen 15 transition metal being copper; and that only 1,2-diazabenzene (Run 17) results in a slight (c) at least one Co-catalyst II having an identity and in rate enhancement, in contrast to 1,3-diazabenzene (Run an amount effective to increase the rate of the hy 25) and 1,4-diazabenzene (Run 23) which actually re droxylation reaction relative to its absence and repre duce the reaction rate (e.g. conversion) over similar sented by at least one of the structural formulae: reaction times. 20 Thus, from the above observations it can be con N (XIa) cluded that the selection of an appropriate Co-catalyst first II will be influenced by consideration of the balance Z5 - 43 between the steric effect an organic substituent will Z4 have on the pyridine ring and any desirable rate en 25 hancement chemically induced by the presence of said O substituent on the pyridine ring, e.g., through alter ations in the electronegative properties of the nitrogen Z8 N (XIb) atOn. 2.9 ' 7 Referring to Table 4, it can be seen that the mere n N Y possession of a tertiary nitrogen by a compound is not R12 indicative of its ability to promote the subject reaction. Thus, triethylamine, (Run 20), N,N,N',N'-tetrame wherein: thylenediamine (Run 26), 1-8-diazanaphthalene (Run 35 (1) in structural formula (XIa): 28), 4,5-diazaphenanthrene (Run 29), 1,3-diazabenzene (a) Z2 to Zó independently represent a member (Run 25), benzimidazoline (Run 24), quinuclidine (Run selected from the group consisting of a methylid 21), 2,2'-bipyridine (Run 22) and 1,4-diazabenzene (Run yne group, a substituted methylidyne group rep 23) actually decreased the reaction rates relative to their resented, by the formula ECR11, and a tertiary absence and/or inhibited the reaction completely. Such 40 nitrogen group; said R11 substituent being Se data are further evidence that the Co-catalysts II de lected from the group consisting of hydroxy, scribed herein operate through a mechanistic route alkyl, aryl, aralkyl and alkaryl; quite different than that observed for tertiary amines in (b) any two of said R11 substituents located on conjunction with conventional tertiary amine promoted adjacent carbons of said Z2 to Z5 groups of struc stoichiometric osmium oxidations of olefins. For exam 45 tural formula (XIa) together can constitute part ple, not only has pyridine been employed for such stoi of a monocyclic or fused bicyclic ring system, chiometric oxidations, but also methyl substituted pyri which partial ring systems are (i) aromatic, or dines, 2,2'-bipyridine and quinuclidine. In fact, 2,2'- heteroaromatic in nature, said heteroatom being bipyridine has actually been observed to induce a much nitrogen, and (ii) completed by, and fused with greater rate enhancement than pyridine for such sotichi 50 parent structure (XIa) through said adjacent ometric oxidations. However, when such materials are carbons of Z2 to Z5 groups; and employed with transition metal in an osmium catalytic (2) in structural formula (XIb): oxidation, the rate of reaction is actually decreased, and (a) Z7 to Z9 independently represent a member in the case of 2,2'-bipyridine, the reaction is practically selected from the group consisting of a methylid terminated. Thus, many of the conventional tertiary 55 yne group, and a substituted methylidyne group amine promoters in stoichiometric oxidations become represented by the formula =CR'1 1 wherein inhibitors in the reaction system of the subject inven R11 is independently selected from the group tion. consisting of alkyl, aryl, aralkyl, and alkaryl; and The principles, preferred embodiments, and modes of (b) R12 is selected from the group consisting of operation of the present invention have been described 60 alkyl, aryl, aralkyl, and alkaryl. in the foregoing specification. The invention which is 2. The process of claim 1 wherein the osmium con intended to be protected herein, however, is not to be taining compound is selected from the group consisting construed as limited to the particular forms disclosed, of osmium oxide, osmium-halide, osmium carbonyl, since these are to be regarded as illustrative rather than ionic osmium oxide, and mixtures thereof; Co-catalyst I restrictive. Variations and changes may be made by 65 comprises a transition metal copper salt having a cation those skilled in the art without departing from the spirit and an anion, wherein said anion is of a member inde of the invention. pendently selected from the group consisting of halide, What is claimed is: carboxylate, aryloate, aryolate, pseudo halide, R1OS, 4,496,778 41 42 HS, R10Se-, HTe-, HSe- and R10Te-, R10 being 12. The process of claim 11 wherein said Co-catalyst alkyl of from about 1 to about 10 carbons. II comprises less than about 15%, by weight, of said 3. The process of claim 2 wherein said catalyst com liquid reaction mixture, and said inert organic solvent position additionally comprises at least one halo-source comprises from about 10 to about 90%, by weight, of having an identity and in an amount effective to in said liquid reaction mixture said inert organic solvent crease at least one of the rate and selectivity of the being dipolar and aprotic. hydroxylation reaction relative to its absence. 13. The process of claim 10 wherein said Co-catalyst 4. The process of claim 3 wherein said halo-source is I is a copper halide salt. selected from the group consisting of halogenated or 14. The process of claim 10 wherein Co-catalyst II is ganic hydrocarbon and halide salt wherein the cation of O selected from the group consisting of 3,5-dimethylpyri said salt is of a member independently selected from the dine, 4-methylpyridine, 4-phenylpyridine, 1 group consisting of alkali metal, alkaline earth metal, methylimidazole, and 1,2-dimethylimidazole. tetrahydrocarbyl ammonium, and tetrahydrocarbyl 15. The process of claim 10 wherein said osmium phosphonium. compound is at least one osmium oxide. 5. The process of claim 1 wherein the olefinic com 5 16. The process of claim 15 wherein said osmium porund contains from about 2 to about 20 carbons. oxide is OsO4. 6. The process of claim 1 wherein said Co-catalyst I is 17. The process of claim 10 wherein said osmium a copper halide salt. compound is at least one osmium-halide. 7. The process of claim 1 wherein Co-catalyst II is 18. The process of claim 17 wherein said osmium selected from the group consisting of pyridine, methyl 20 halide is represented by the structural formula OsX3 pyridine, dimethylpyridine, 4-phenylpyridine, 1,2- wherein X is selected from the group consisting of Br, I, diazabenzene, methylimidazole, dimethylimidazole, and Cl, and mixtures thereof. mixtures thereof. 19. The process of claim 18 wherein X is selected 8. The process of any one of claims 3, 4, 6 and 7 from the group consisting of Br and Cl. wherein the identity and amount of the osmium in the 25 20. The process of claim 10 wherein the osmium osmium compound, Co-catalyst I, and halo-source, in compound is at least one osmium carbonyl. said catalyst composition, are controlled to achieve in 21. The process of claim 20 wherein said osmium said composition a molar ratio of osmium:transition carbonyl is Os3(CO)12. metal of Co-catalyst I: halogen in the halo-source of 22. The process of claim 10 wherein said osmium from about 1:1:1 to about 1:100:1000. 30 compound is adsorbed on a support. 9. The process of claim 7 wherein said Co-catalyst II 23. The process of claim 10 wherein said liquid reac is selected from the group consisting of pyridine, 3,5- tion mixture further comprises a halo-source soluble in dimethylpyridine, 2,4-dimethylpyridine, 2-methylpyri said liquid reaction mixture having an identity and in an dine, 4-methylpyridine, 4-phenylpyridine, 1 amount effective to increase at least one of the rate and methylimidazole, 1,2-dimethylimidazole, and mixtures 35 selectivity of the hydroxylation reaction relative to the thereof. absence of said halogen in said halo-source. 10. A process for directly hydroxylating olefins 24. The process of claim 23 wherein said halo-source which comprises admixing to form a liquid reaction is selected from the group consisting of osmium-halide; mixture comprising: copper halide; alkali metal halide; alkaline earth metal (1) at least one olefinic compound having at least one 40 halide; tetrahydrocarbyl ammonium halide; tetrahy ethylenic unsaturation; drocarbylphosphonium halide; halogenated hydrocar (2) at least one catalytically active osmium containing bon wherein the hydrocarbyl portion is selected from compound; saturated aliphatic, saturated alicyclic, and aromatic; (3) at least one transition metal containing Co-catalyst and mixtures thereof; and wherein in said liquid reaction I having an identity and in an amount effective to 45 mixture the mole ratio of osmium:copper:halogen of increase at least one of the rate and selectivity of said halo-source present therein, is from about 1:10:100 said hydroxylation reaction relative to its absence, to about 1:50:500. wherein said transition metal is copper; 25. The process of claim 23 wherein said halo-source (4) at least one Co-catalyst II having an identity and is selected from the group consisting of copper halide; in an amount effective to increase at least one of the 50 alkali metal halide; alkaline earth metal halide; tetrahy rate and selectivity of the hydroxylation reaction drocarbyl phosphonium halide; tetrahydrocarbyl am relative to its absence, said Co-catalyst II compris monium halide; halogenated hydrocarbon wherein the ing at least one member selected from the group hydrocarbyl portion thereof is selected from saturated consisting of pyridine, 3,5-dimethylpyridine, 2,4- aliphatic, saturated alicyclic and aromatic; and mixtures dimethylpyridine, 4-methylpyridine, 4-phenylpyri 55 thereof, and wherein said liquid reaction mixture the dine, 2-methylpyridine, 1-methylimidazole, and mole ratio of osmium:copper:halogen present in said 1,2-dimethylimidizole; halo-source therein, is from about 1:15:20 to about (5) an oxygen containing gas; and 1:40:200, (6) water in at least a stoichiometric molar ratio with 26. The process of any one of claims 10 to 25 wherein the molar amount of ethylenic unsaturation to be 60 said liquid reaction mixture is homogeneous, and hydroxylated in the olefinic compound; said admix wherein in said liquid reaction mixture the osmium ing being conducted in a manner and under condi compound is present in an amount sufficient to achieve tions sufficient to catalytically convert at least one a ratio of moles of osmium in the osmium compound to of said ethylenic unsaturation directly to its corre moles of ethylenic unsaturation to be hydroxylated of sponding diol. 65 from about 1 x 10-2:1 to about 1X 10-6:1; Co-catalyst I 11. The process of claim 10 wherein said liquid reac is present in an amount sufficient to achieve a ratio of tion mixture additionally comprises at least one inert moles of osmium in the osmium compound to moles of organic solvent. copper in Co-catalyst I of from about 1:500 to about 1:5; 4,496,778 43 44 and Co-catalyst II is present in an amount sufficient to 28. The process of claim 27 wherein said olefin is achieve a ratio of the moles thereof to the moles of selected from the group consisting of ethylene, propy copper in the Co-catalyst I of from about 2:1 to about lene and mixtures thereof. 10:1; water is present in an amount sufficient to achieve 29. The process of claim 11 wherein the inert organic a mole ratio of water to ethylenic unsaturation to be 5 solvent comprises from about 20 to about 80%, by hydroxylated of from about 1:1 to about 10:1; and inert weight, of the reaction mixture and is selected from the organic solvent, when present, is present in an amount group consisting of sulfolane, acetonitrile, N,N-dime of from about 20 to about 80%, by weight, based on the thylacetamide, N,N-dimethylformamide, hydroxylated weight of said reaction mixture. product and mixtures thereof. 27. The process of claim 10 wherein said reaction 10 30. The process of claim 29 wherein Co-catalyst I is mixture is substantially homogeneous and wherein in CuBr2; Co-catalyst II is pyridine, and the osmium com said reaction mixture: the osmium containing com pound is selected from the group consisting of OsO4, pound is selected from the group consisting of OsO4, OsBr3 and mixtures thereof. OsBr3, OsCl3, Os3(CO)12 and mixtures thereof; the Co 31. The process of claim 10 wherein the hydroxyl catalyst I is selected from the group consisting of 15 ation reaction temperature is from about 40 to about CuBr2, CuCl2, and mixtures thereof, and Co-catalyst II 250 C., and the reaction pressure is from about 300 to comprises less than about 5%, by weight, of the reac about 1500 psig. tion mixture. *k ck ck k ck

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