IIIHHHHHHHHHHHHHHIII US005l 18822A United States Patent (19) 11) Patent Number: 5,118,822 Shum et al. (45) Date of Patent: Jun. 2, 1992

(54) OLEFIN EPOXIDATION USING A 4,564,715 1/1986 Briggs et al...... 568/867 PERRHENATE CATALYST AND AN 4,667.045 5/1987 Briggs et al...... 556/20 ORGANIC HYDROPEROXIDE 4,822,899 4/1989 Groves et al. ... 549/533 4,864,041 9/1989 Hill ...... 549/529 75 Inventors: Wilfred P. Shum, West Chester; 4,982,021 1/1991 Best et al...... 568/867 Haven S. Kesling, Jr., Drexel Hill, 4,987,226 1/1991 Buchler et al...... 540/145 both of Pa. FOREIGN PATENT DOCUMENTS 73) Assignee: Arco Chemical Technology, L.P., 308101 3/1989 European Pat. Off. . Wilmington, Del. 308791 3/1989 European Pat. Off. . 1 ADD. : 767,594 3902357 8/1990 Fed. Rep. of Germany . 2 ppi. No.: 767,59 7513859 4/1976 Netherlands ...... 549/529 22 Filed: Sep. 30, 1991 (51 Int. Cl.5 CO7D 301/19 OTHER PUBLICATIONS 52 U.S.nt. C. C...... s.49/s29569/909.8 Kollar, Preprints, Div. Pet Chem, 106 (1978). 58) Field of Search ...... 549/529 Ly et al., Chem. Ing. Tecfn. 61(8), 646 (1989). 1 - . Jorgensen, Chem. Rev. 89(3), 431 (1989). (56) References Cited Herrmann, J. Organomet. Chem. 382, 1 (1990). U.S. PATENT DOCUMENTS Sheldon, J. Mol. Cat. 7, 107 (1980). 3.316,279 4/1967 Fenton ...... oss Rummel et al., Oxid Commun. 6,319 (1984). 3. 27 E. SA- - - - - 2.: Primary Examiner-J. E. Evans 3,391.214yav WWs 7/1968 Fetterly11CK ...... - a g; Attorney, Agent, or Firm-Stephenfrn D. Harper 3,475,498 10/1969 Choo ...... 549/529 (57) ABSTRACT 3,489,775 l/1970 de Rochet al. . ... 549/529 o 3,518.285 6/1970 Fenton et al...... 260/348.5 Olefins are oxidized to epoxide compounds by contact 3.536,732 10/1970 Borchert et al...... 549/529 ing the olefins with organic hydroperoxides in the pres 3,745,178 7/1973 White...... 549/529 ence of rhenium catalysts comprised of perrhenate an 3,778,451 12/1973 Poite...... 2. ions and organopnicogen-containing cations. High 3,849,451 1 1/1974 Stein et al...... 549/529 yields of epoxides are attained, particularly when the 3,860,6623,931,249 1/1976l/1975 StoutzenbergerKollar ...... 549/529549/59 olefinlef substrateb bbears an aromatic substituent.bsti 4,024,165 5/1977 Shryne et al...... 260/348.5 4,418,203 11/1983 Kim ...... 549/531 29 Claims, No Drawings 5, 18,822 1. 2 oxides are either inactive or nonselective in the oxida OLEFIN EPOXIDATION USING A PERRHENATE tion of olefins in the presence of oxidizing agents such as CATALYST AND AN ORGANIC t-butyl hydroperoxide. HYDROPEROXIDE To date, rhenium compounds such as rhenium hep toxide have thus been primarily used to promote de FIELD OF THE INVENTION composition reactions of hydroperoxides rather than as This invention relates to methods wherein an olefin oxidation catalysts. For example, the process described may be oxidized to an epoxide. More particularly, this in European Pat. Appl. No. 308, 101 employs rhenium invention pertains to catalytic epoxidation processes compounds to catalyze the decomposition of t-butyl employing organopnicogen-containing perrhenate O hydroperoxide to t-butyl alcohol. Jpn. Kokai No. compounds as catalysts and organic hydroperoxides as 63-277,640 (Chem. Abst. 110:172753d) teaches cyclo oxidizing agents. hexyl hydroperoxide decomposition to cyclohexanol or cyclohexanone using rhenium heptoxide. U.S. Pat. No. BACKGROUND OF THE INVENTION 4,297,518 describes the use of rhenium heptoxide to Epoxides such as ethylene oxide, propylene oxide, 15 catalyze the rearrangement of cumene hydroperoxide 1,2-butene oxide and the like are useful intermediates to phenol and acetone. for the preparation of a wide variety of products. The It is thus apparent that rhenium compounds have oxirane functionality in such compounds is highly reac heretofore been found to be of little utility as catalysts tive and may be ring-opened with any number of nu for the epoxidation of olefins using alkyl hydroperox cleophilic reactants. For example, epoxides may be 20 ides as the source of oxygen, owing to the tendency of hydrolyzed to yield glycols useful as anti-freeze compo such compounds to favor hydroperoxide decomposi nents, food additives, or reactive monomers for the tion over olefin epoxidation. We have now found that preparation of condensation polymers such as polyes certain perrhenate compounds, in contrast to the rhe teS. nium compounds employed in the prior art, are excel Polyether polyols generated by the ring-opening 25 lent olefin epoxidation catalysts and permit the prepara polymerization of epoxides are widely utilized as inter tion of epoxides with high selectivity and minimal un mediates in the preparation of polyurethane foams, productive hydroperoxide decomposition. The ability elastomers, sealants, coatings, and the like. The reaction of organopnicogen-containing perrhenate compounds of epoxides with alcohols provides glycol ethers, which to effectively catalyze epoxidation reactions was com may be used as polar solvents in a number of applica 30 pletely unexpected in view of their ineffectiveness when tions. hydrogen peroxide is employed as the oxidant, as taught Many different methods for the preparation of epox in German Pat. No. 3,902,357. ides have been developed. One such method involves The perrhenate catalysts of this invention are particu the epoxidation of an olefin in a liquid phase reaction larly suitable for use in biphasic reaction media contain using an organic hydroperoxide as the oxidizing agent 35 ing water and thus can be employed in epoxidations and certain transition metal compounds as catalyst. wherein an aqueous organic hydroperoxide solution is Generally speaking, Group IVB, VB, and VIB transi the source of the required oxidant. The high selectivity tion metal compounds have been found to have the to epoxide realizable in such systems was especially highest activity and selectivity in olefin epoxidation surprising in view of the fact that organopnicogen-con reactions using organic hydroperoxides. Metals having 40 taining perrhenate compounds have previously been low oxidation potentials and high Lewis acidity in their highest oxidation states are superior epoxidation cata used to catalyze the hydrolysis of epoxides to glycols as lysts, according to Sheldon, J. Mol. Cat. 7, 107(1980). disclosed, for example, in U.S. Pat. No. 4,564,715. Molybdenum, tungsten, titanium, and vanadium com SUMMARY OF THE INVENTION pounds thus have generally been found to be the most 45 useful catalysts for the reaction of an organic hydroper This invention provides a process for epoxidizing an oxide with an olefin. olefin comprising contacting the olefin with an organic Sheldon found that rhenium heptoxide, in contrast to hydroperoxide in the presence of a rhenium catalyst other transition metal compounds, caused rapid, non comprised of a perrhenate anion and an organopnico productive decomposition of the hydroperoxide. Thus, 50 gen-containing cation effective to form an epoxide of an attempt to epoxidize 1-octene with t-butyl hydroper the olefin. oxide using rhenium heptoxide gave complete conver In one particular embodiment, the invention provides sion of the hydroperoxide to the corresponding alcohol a process for epoxidizing an olefin wherein at least one but none of the desired epoxide product. Kollar U.S. of the ethylenically unsaturated functional groups of the Pat. No. 3,351,635 (Table I); Preprints, Dev. Pet. Chem. 55 olefin bears an aromatic substituent. The process com 106(1978) also reported extremely low yields of epox prises contacting a secondary or tertiary hydroperoxide ide when the use of a rhenium catalyst in an epoxidation having the general structure reaction was attempted, apparently due to the very rapid decomposition of the hydroperoxide catalyzed by Ril the rhenium compound. Low selectivity to epoxide was 60 similarly observed using rhenium decacarbonyl as cata R12-C-OOH lyst, cyclohexene as the olefin substrate, and t-butyl kis hydroperoxide as the oxidant Rummel et al. Oxid Commun. 6,319(1984)). Jorgensen, in a recent review of wherein R11, R12, and R3 are the same or different and transition metal catalyzed epoxidations Chem. Rev. 89, 65 are selected from the group consisting of hydrogen, 431(1989)), concludes that rhenium complexes are poor methyl, ethyl, and phenyl in the presence of a rhenium epoxidation catalysts using t-butyl hydroperoxide as catalyst having the general formula oxidant. DE 3,902,357 similarly teaches that rhenium 5,118,822 3. 4. R, R, and Rare hydrogen, and Pn is nitrogen, phos phorus, or arsenic. Examples of C1-C20 linear, wherein R, R, R2, and R3 are the same or different and branched, or cyclic alkyl substituents include, but are are selected from the group consisting of hydrogen, not limited to, methyl, ethyl, propyl, butyl (n-sec-iso-, C1-C20 linear, branched, or cyclic alkyl, C6-C20 aryl, tert-), pentyl (and C5H11 isomers), isopropyl, hexyl (and and C7-C20 aralkyl, with the proviso that not all of R, C6H13 isomers), heptyl (and C7H11 isomers), octyl (and R, R2, and R3 are hydrogen, and Pn is N, P, or As, C10H17 isomers), nonyl (and C9H19 isomers), decyl (and effective to form an epoxide of the olefin. C10H2 isomers), undecyl (and C11H23 isomers), dodecyl In another embodiment, a process for epoxidizing an (and C12H25 isomers), tridecyl(and C13H27 isomers), olefin is provided which comprises contacting the olefin O tetradecyl (and C14H29 isoners), pentadecyl (and with an organic hydroperoxide in the presence of cata C15H3 isomers), hexadecyl (and C6H33 isomers), hep lytically effective amounts of an alkali metal perrhenate tadecyl (and C17H35 isomers), octadecyl (and C18H37 and an organopnicogen halide salt. Optionally, this isomers), nonadecyl (and C19H39 isoners), eicosyl (and process is carried out in the presence of water and a C20H39 isomers), cyclopentyl, cyclohexyl, cyclooctyl, water-inmiscible organic solvent such that a biphasic 15 and the like. Examples of C6-C20 aryl substituents in reaction mixture is formed. clude phenyl, naphthyl, tolyl, xylyl, mesityl, anthryl, DETAILED DESCRIPTION OF THE cumenyl, and the like. Suitable C7-C20 aralkyl substitu INVENTION ents include benzyl, phenethyl, naphthylethyl and the The catalyst employed in the process of this invention like. The organic substituents may contain, in addition is an organopnicogen-containing perrhenate. Such con 20 to carbon and hydrogen, other elements such as oxygen, pounds are well-known and are characterized by having nitrogen, halide (e.g., bromide, chloride), or sulfur in at least one perrhenate anion (ReO4) and at least one various functional groups such as ester, sulfide, hy organopnicogen-containing cation. The cation is com droxyl, amine, cyano, nitro, ether, ketone, and the like prised of at least one pnicogen, that is, an element of 25 provided these other elements or functional groups do Group VA of the periodic table and at least one organic not detrimentally interfere with the catalytic activity of substituent bonded to or associated with the pnicogen. the organopnicogen-containing perrhenate compound. "Organic substituent" in this context refers to radicals The R groups may be bonded to each other; thus, the containing, at a minimum, carbon and hydrogen. Pref organic substituents attached to the pnicogen may be erably, the pnicogen is bonded to or associated with a trimethylene, tetramethylene, pentamethylene, hexa carbon atom of the organic substituent. The pnicogen is 30 methylene, heptamethylene, cyclohexylene, or other most preferably either nitrogen, phosphorus, or arsenic, such groups having the general structure--R-)- wherein but can also be antimony or bismuth. The cation may -(-R-)- replaces two of the R groups in the formulae given contain more than one type of pnicogen (e.g., one nitro above as well as substituted derivatives thereof. The gen and one phosphorus, one phosphorus and one ar organic substituents may also comprise an aromatic senic). While either one, two, three, or four organic 35 ring. Thus, suitable organopnicogen-containing cations substituents may be bonded to or associated with each include pyridinium, bipyridinium, acridinium, and the pnicogen in the cation, it is preferred that the cation be like and substituted derivatives thereof. quaternary in structure with four such substituents Alternatively, the organopnicogen-containing cation being associated with the pnicogen. Without wishing to be bound by theory, it is believed that the organopnico has the general formula gen-containing cation helps to solubilize the perrhenate anion in the organic-based reaction mixture containing olefin, organic hydroperoxide, and, optionally, organic wherein R4, R5, R6, R7, R8, R9, and R10 are the same or solvent. Thus, in one embodiment of the process, the 45 different and are selected from the group consisting of reaction mixture is homogeneous. This solubilization is hydrogen, C1-C20 linear, branched, or cyclic alkyl, thought to be partially responsible for the favorable catalytic activity of the perrhenate compounds used C6-C20 aryl, and C7-C20 aralkyl, with the proviso that herein, as alkali metal perrhenates are generally insolu R7 is not hydrogen, and Pn2 and Pn are the same or ble in such mixtures. Preferably, the organopnicogen different and are N, P, or As. The R substituents may be containing cation is selected such that the resulting 50 any of the types taught hereinabove in reference to the perrhenate catalyst has a solubility in the reaction mix monopnicogen-containing embodiment of the inven ture at the operable reaction temperature of at least tion. The R7 substituent linking the two pnicogens may, about 1000 ppm. However, the ability of rhenium spe for example, be any substituent in the series (CH2) cies to function as effective epoxidation catalysts is not wherein n is an integer of from 1 to 20 or any substituted related solely to their solubility in organic media since 55 derivative or branched or cyclic isoner thereof as well rhenium heptoxide has appreciable solubility in typical as a substituent such as phenylene, cyclohexylene, phe organic solvents and yet is a very poor catalyst for nylmethylene, phenyldimethyl, and the like. olefin epoxidation using organic hydroperoxide as oxi The organic substituents in the cation component of dant. this invention may, particularly where the pnicogen is Suitable organopnicogen-containing cations may other than nitrogen, alternatively be selected such that have the general formula R is a heteroatom-containing organic group wherein the heteroatom is bonded to or associated with the pnicogen. In this embodiment, the heteroatom may be oxygen, nitrogen, or the like. For example, alkoxy, wherein R, R, R2, and R3 are the same or different and 65 phenoxy, aralkyoxy, or amino groups can be employed are selected from the group consisting of hydrogen, as an organic substituent. C1-C20 linear, branched, or cyclic alkyl, C6-C20 aryl, Specific illustrative examples of organopnicogen and C714 C20 aralkyl, with the proviso that not all of R, containing cations suitable for use in the process of this 5,118,822 5 6 invention include, but are not limited to, tetrahydrocar arsonium, tridodecyl arsonium, trioctadecyl arsonium, byl ammoniums such as tetramethyl ammonium, tetra and the like; dihydrocarbyl arsoniums, e.g., dimethyl ethyl annonium, tetra-n-propyl ammonium, tetra-n- arsonium, diethyl arsonium, di-n-butyl arsonium, di-n- butyl ammonium, tetra-isobutyl ammonium, trimethyl hepty) arsonium, diphenyl arsonium, dibenzyl arso butyl ammonium, tetraheptyl ammonium, tetraphenyl nium, didodecyl arsonium, dioctadecyl arsonium, and ammonium, tetrabenzyl ammonium, tetradodecyl am the like; hydrocarbyl arsoniums, e.g., methyl arsonium, monium, tetraoctadecyl ammonium, 1-ethylpyridinium, n-butyl arsonium, dodecyl arsonium, octadecyl arso 1-ethylquinolinium, 1-ethylquinaldinium, 1-hexadecyl nium, phenyl arsonium, benzyl arsonium, and the like. pyridinium, hexadecyltrimethyl ammonium, methyl The analogous antimony and bismuth-containing cati triphenyl phosphonium, 1-(m-nitrobenzyloxy)methyl)- O ons may also be of utility. pyridinium, nonyltrimethyl ammonium, 1-phenethyl-2- Examples of polypnicogen-containing cations include picolinium, tetrakis(2-hydroxyethyl)ammonium, trica N,N'-bis(trimethyl)propylene diammonium, N,N'-bis(- prylmethyl ammonium, triethylphenyl ammonium, tri triphenyl)propylene diammonium, N,N'-bis(trioc octyl propyl ammonium, benzyldimethyl hexadecyl tadecyl)propylene diammonium, N,N'-diheptyl-4,4'- ammonium, benzyldimethyl phenyl ammonium, benzyl 15 bipyridinium, N,N'-bis(trimethyl) ethylene diammo triethyl ammonium, benzyltrimethyl ammonium, bis(2- nium, P.P'-bis(trimethyl)propylene diphosphonium, hydroxyethyl)dimethyl ammonium, (2-chloroethyl)- As, As'-bis(trimethyl)propylene diarsonium, 4 trimethyl ammonium, decyltrimethyl ammonium, N,N',N',N'-tetraethyl-phenylene diammonium, and the didodecyldimethyl ammonium, dimethyl di-octadecyl like. ammonium, dodecyl trimethyl ammonium, ethyl hexa 20 Organopnicogen-containing perrhenate compounds decyl dimethyl ammonium, and the like; trihydrocarby suitable for use in the process of this invention may be ammoniums, e.g., trimethyl ammonium, triethyl ammo prepared using any of the methods known in the art. nium, triphenyl ammonium, tridodecyl ammonium, Such methods are described, for example, in the follow trioctadecyl ammonium, and the like; dihydrocarbyl ing publications, all of which are incorporated herein by ammoniums, e.g., dimethyl ammonium, diethyl ammo 25 reference in their entirety: Williams et al., Inorg. Synth. nium, di-n-butyl ammonium, di-n-heptyl ammonium, 26, 386(1989); Burkert et al., Z. Naturforsch, B: Chem. diphenyl ammonium, dibenzyl ammonium, didodecyl Sci. 45(6), 725(1990); Bolshakov et al., Izy. Vyssh. Ucheb. ammonium, dioctadecyl ammonium, and the like; hy Zaved, Khim. Tekhnol. 15(3), 334(1972); Bondarenko et drocarbyl ammoniums, e.g., methyl ammonium, n-butyl al., Zh. Obsh. Khim. 53, 1778(1983), Kholopova et al., ammonium, dodecyl ammonium, octadecyl ammonium, 30 Zh. Obsh. Khim, 53, 1285(1983), and Okrasinski et al., J. phenyl ammonium, benzyl ammonium, and the like; Inorg. Nucl. Chem. 36(8), 1908(1974). Mixtures of or tetrahydrocarbyl phosphoniums, e.g., tetramethyl phos ganopnicogen-containing perrhenate compounds may phonium, tetraethyl phosphonium, tetra-n-propyl phos be employed as catalyst in the process of this invention phonium, tetra-n-butyl phosphonium, tetra-isobutyl if desired. phosphonium, trimethyl butyl phosphonium, tetrahep 35 The organopnicogen-containing perrhenate catalyst tyl phosphonium, tetraphenyl phosphonium, tetraben may be introduced into the reaction system as a pre zyl phosphonium, tetradodecyl phosphonium, tetraoc formed compound or, in another embodiment, in pre tadecyl phosphonium, chloromethyl triphenyl phos cursor form convertible to the active catalyst by chemi phonium, methoxymethyl triphenyl phosphonium, 2 cal reaction. In one preferred variation of the latter chloroethyl triphenyl phosphonium, cyclopropyl 40 embodiment, an alkali metal perrhenate salt and a halide methyl triphenyl phosphonium, 3-phenylpropyl tri salt of the organopnicogen-containing cation are simul phenyl phosphonium, 2-butyl triphenyl phosphonium, taneously employed such that an organopnicogen-con cyclohexyl triphenyl phosphonium, n-hexadecyl tri taining perrhenate catalyst is generated in situ. A sepa phenyl phosphonium, isoamyl triphenyl phosphonium, rate catalyst preparation step thus is not required. Other benzyl triphenyl phosphonium, 4-n-butoxybenzyl tri 45 variations of this approach will be apparent to those phenyl phosphonium, 4-fluorobenzyl triphenyl phos skilled in the art wherein the perrhenate anion is intro phonium, 2-nitrobenzyl triphenyl phosphonium, 1 duced in the form of an ammonium, alkaline earth, or naphthylmethyl triphenyl phosphonium, triphenyl heavy metal salt and the organopnicogen-containing methyl triphenyl phosphonium, and the like; trihydro cation is introduced in the form of a halide, nitrate, carbyl phosphoniums, e.g., trimethyl phosphonium, 50 nitrite, sulfate, sulfite, chlorate, chlorite, or carboxylate triethyl phosphonium, triphenyl phosphonium, tridode salt reactive with the perrhenate salt under the condi cyl phosphonium, trioctadecyl phosphonium, and the tions employed. In this embodiment, it is preferred to like; dihydrocarbyl phosphoniums, e.g., dimethyl phos use approximately equivalent (i.e., stoichiomatric) phonium, diethyl phosphonium, di-n-butyl phospho amounts of each precursor component. For example, nium, di-n-heptyl phosphonium, diphenyl phospho 55 where the alkali metal perrhenate salt is potassium per nium, dibenzyl phosphonium, didodecyl phosphonium, rhenate and the organopnicogen halide salt is tetra-n- dioctadecyl phosphonium, and the like; hydrocarbyl butyl ammonium chloride, it is desirable that the molar phosphoniums, e.g., methyl phosphonium, n-butyl ratio of the two be from about 4:1 to 1:4. phosphonium, octadecyl phosphonium, phenyl phos In another embodiment of this invention, the or phonium, benzyl phosphonium, and the like. ganopnicogen-containing cation may be anchored or Also suitable are tetrahydrocarbyl arsoniums such as immobilized on a solid support such that the reaction tetrahydrocarbyl arsoniums e.g., tetramethyl arsonium, mixture during epoxidation is heterogeneous. The sup tetraethyl arsonium, tetra-n-propyl arsonium, tetra-n- port may be inorganic in character such as alumina, butyl arsonium, tetra-isobutyl arsonium, trimethylbutyl clay, zeolite or silica gel or alternatively may be an arsonium, tetrahepty arsonium, tetraphenyl arsonium, 65 organic polymer. The support may have the cation tetrabenzyl arsonium, tetradodecyl arsonium, tetraocta affixed thereto through adsorption, reaction, or graft decyl arsonium, and the like; trihydrocarbyl arsoniums, polymerization. Such supports comprising organop e.g., trimethyl arsonium, triethyl arsonium, triphenyl nicogen-containing cations are well known and are 5,118,822 7 8 described, for example, in the following representative enes, and other polyunsaturated substrates thus may be publications, all of which are incorporated hereby by used. Other examples of suitable substrates include un reference in their entirety: U.S. Pat. Nos. 4,982,021 and saturated fatty acids or fatty acid derivatives such as 4,430,496; Japanese Kokai No. 50-32085 and 52-26386; esters or glycerides and oligomeric or polymeric unsat P. Tundo et al., J. Am. Chem. Soc. 104, 6547(1982); P. urated compounds such as polybutadiene. Tundo et al., J. Am. Chem. Soc. 104, 6551 (1982); Ger The olefin may contain substituents other than hydro man Pat. No. 2,433,409; U.S. Pat. Nos. 4,417,066 and carbon substituents such as halide, carboxylic acid, 4,410,669. The preparation of perrhenate-containing ether, hydroxy, thiol, nitro, cyano, ketone, ester, anhy catalysts from such supports may be carried out using dride, amino, and the like. methods similar to those described for the analogous O Exemplary olefins suitable for use in the process of vanadium, molybdenum, and titanium-containing sup this invention include ethylene, propylene, the butenes, ported catalysts of U.S. Pat. No. 4,982,021, the teach butadiene, the pentenes, isoprene, 1-hexene, 3-hexene, ings of which are incorporated herein by reference in 1-heptene, 1-octene, diisobutylene, 1-nonene, l-tetra their entirety. decene, pentamyrcene, camphene, 1-undecene, l The amount of organopnicogen-containing perrhe 15 dodecene, 1-tridecene, 1-tetradecene, l-pentadecene, nate used in the process of this invention is not critical, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadec but should be sufficient to catalyze the oxidation of the ene, 1-eicosene, the trimers and tetramers of propylene, olefin substrate by the organic hydroperoxide. Molar polybutadiene, polyisoprene, cyclopentene, cyclohex ratios of olefin:rhenium of from about 10,000:1 to 1:1 ene, cycloheptene, cyclooctene, cyclooctadiene, cy will generally be appropriate for achieving useful yields 20 of epoxide within commercially feasible reaction times, clododecene, cyclododecatriene, dicyclopentadiene, owing to the relatively high catalytic activity of the methylenecyclopropane, methylenecyclopentane, me organopnicogen-containing catalyst. Preferably, how thylenecyclohexane, vinylcyclohexane, vinyl cyclohex ever, the olefin:rhenium molar ratio is from about ene, methallyl ketone, allyl chloride, ally bromide, 2000:1 to about 50:1. 25 acrylic acid, methacrylic acid, crotonic acid, vinyl The organic hydroperoxide to be used as the oxidiz acetic acid, crotyl chloride, methallyl chloride, the ing agent in the process of this invention may be any dichlorobutenes, allyl alcohol, allyl carbonate, allyl organic compound having at least one hydroperoxy acetate, alkyl acrylates and methacrylates, diallyl male functional group (-00H). Secondary and tertiary hy ate, diallyl phthalate, unsaturated triglycerides such as droperoxides are preferred, however, owing to the 30 soybean oil, and unsaturated fatty acids, such as oleic higher instability and greater safety hazards associated acid, linolenic acid, linoleic acid, erucic acid, oleos with primary hydroperoxides. The organic hydroper tearic acid, myristic acid, palmitic acid, and ricinoleic oxide preferably has the general structure acid and their esters. The process of this invention is particularly well suited for the epoxidation of olefins wherein the ethyl Rll 35 enically unsaturated functional group of the olefin bears R2-COOH at least one aromatic substituent. The aromatic substitu ent may be phenyl, substituted phenyl such as halo his phenyl, alkyl phenyl, or alkoxy phenyl, naphthyl, or wherein R11, R12, and R13 are the same or different and 40 substituted naphthyl, or the like. Particularly preferred are selected from the group consisting of hydrogen, are alkenyl aromatic compounds, especially those hav methyl, ethyl, and phenyl. Exemplary organic hydro ing the general structure peroxides include t-butyl hydroperoxide, t-amyl hydro peroxide, cumene hydroperoxide, ethylbenzene hydro peroxide, cyclohexane hydroperoxide, methyl cyclo 45 hexane hydroperoxide, tetralin hydroperoxide, isobutyl benzene hydroperoxide, isopropyl hydroperoxide, ethyl naphthalene hydroperoxide, and the like. Mixtures of organic hydroperoxides may also be employed. The wherein at least one of R, R2, R3, or R“is an aromatic amount of organic hydroperoxide is not critical, but 50 substituent (e.g., phenyl, naphthyl, anthryl and substi most suitably the molar ratio of olefin:organic hydro tuted derivatives thereof) and the remaining R substitu peroxide is suitably from about 100:1 to 1:100 when the ents are selected from the group consisting of hydrogen olefin contains one ethylenically unsaturated group. and C1-C8 alkyl. Examples of alkenyl aromatic com The molar ratio of ethylenically unsaturated groups in pounds include styrene, a-methyl styrene, A-methyl the olefin substrate to organic hydroperoxide is more 55 styrene, divinyl benzene, 1,2-dihydronaphthalene, in preferably in the range of from 20:1 to 1:5. One equiva dene, stilbene, cinnamyl alcohol, 2-methyl-1-phenyl-1- lent of hydroperoxide is theoretically required to oxi propene, 2-methyl-3-phenyl-2-propen-1-ol, cinnamyl dize one equivalent of a mono-unsaturated olefin sub acetate, cinnamyl bromide, cinnamyl chloride, 4-still strate, but it may be desirable to employ an excess of benemethanol, ar-methyl styrene, ar-ethyl styrene, ar one reactant to optimize selectivity to the epoxide. 60 tert-butyl styrene, ar-chlorostyrene, 1,1-diphenylethy The olefin substrate may be any organic compound lene, vinyl benzyl chloride, vinyl naphthalene, vinyl having at least one ethylenically unsaturated functional benzoic acid, ar-acetoxy styrene, ar-hydroxy styrene group (i.e., a carbon-carbon double bond) and may be (i.e., vinyl phenol), 2- or 3-methyl indene, 2,4,6-trimeth an aromatic, aliphatic, mixed aromatic-aliphatic (e.g., ylstyrene, 1-phenyl-1-cyclohexene, 1,3-diisopropenyl aralkyl), cyclic, branched or straight chain olefin. Pref 65 benzene, vinyl anthracene, vinyl anisole, and the like. erably, the olefin contains from 2 to 30 carbon atoms An organic solvent or mixture of organic solvents (i.e., a C2-C30 olefin). More than one carbon-carbon may additionally be present when the olefin is contacted double bond may be present in the olefin; dienes, tri with the hydroperoxide and catalyst. The solvent may 5,118,822 10 be used to dilute, disperse, or dissolve the components the invention is not critical and typically can be varied of the reaction mixture, thus providing better tempera from 1 to 75 weight % of the total reaction mixture. ture control or faster reaction rates. The identity of the The reaction temperature is not critical, but should be solvent may advantageously be altered to control the sufficient to accomplish substantial conversion of the rate or selectivity of the epoxidation process. Examples 5 olefin to epoxide within a reasonably short period of of suitable organic solvents include, but are not limited time. It is generally advantageous to carry out the reac to, aliphatic hydrocarbons (e.g., hexane, cyclohexane, tion to achieve as high a hydroperoxide conversion as petroleum ether), aromatic hydrocarbons (e.g., ben possible, preferably at least 50% and desirably at least Zene, toluene, xylene, ethyl benzene, naphthalene, cu 90%, consistent with reasonable selectivities. The opti mene), and halogenated hydrocarbons (e.g., methylene 10 mum reaction temperature will be influenced by cata chloride, chloroform, carbon tetrachloride, trichloro lyst activity, olefin reactivity, reactant concentrations, ethane, chlorobenzene). The amount of organic solvent and type of solvent employed, among other factors, but is not critical, but typically will be from about 5 to 95 typically will be in a range of from about 0' C. to 150 weight % of the total reaction mixture. It is generally C. More preferably, the temperature will be from about 15 20 C. to 100 C. Reaction times of from about 10 min desirable to carry out the process of this invention utes to 48 hours will typically be appropriate, depend under an inert atmosphere, that is, in the absence of ing upon the above-identified variables. Although sub Oxygen. atmospheric pressures can be employed, the reaction is An unexpected advantage of the process of this in preferably performed at atmospheric pressure or at vention is the reduced tendency of the organopnicogen 20 elevated pressure (typically, not greater than about containing perrhenate catalyst as compared to other 2,000 psig). Generally, it will be desirable to maintain epoxidation catalysts to be inhibited by water, alcohol, the reaction components as a liquid phase mixture. ethers, or other Lewis bases in the reaction mixture. It The process of this invention may be carried out in a is well known that other transition metal epoxidation batch, continuous, or semi-continuous manner using catalysts such as molybdenum coordinate strongly with 25 any appropriate type of reaction vessel or apparatus. Lewis bases, thereby reducing the rate of reaction. Known methods for conducting transition metal cata Since the organic hydroperoxide is converted to an lyzed epoxidations of olefins using organic hydroperox alcohol as the epoxidation reaction proceeds, pushing ides will generally also be suitable for use in this pro the epoxidation to high conversion can consequently be cess. Thus, the reactants may be combined all at once or difficult. This is a particular problem if a relatively high 30 sequentially. For example, the organic hydroperoxide boiling epoxide is the desired product, since such epox may be added incrementally to the reaction zone. Once ides are difficult to separate from a reaction mixture the epoxidation has been carried out to the desired de containing large amounts of unreacted olefin and hy gree of conversion, the desired epoxide product may be droperoxide. In contrast, the use of the organopnico separated and recovered from the reaction mixture gen-containing perrhenate catalysts of this invention 35 using any appropriate technique such as fractional dis permits high yields of epoxide to be attained in a batch tillation, extractive distillation, liquid-liquid extraction, type process since such catalysts are inhibited to a much crystallization, or the like. The co-product of the reac lesser extent than prior art epoxidation catalysts. Thus, tion will generally be the corresponding alcohol de alcohols may be used as a reaction solvent, including rived from the organic hydroperoxide and may simi those alcohols corresponding to the organic hydroper larly be separated and recovered for use as a valuable oxide component of the reaction mixture such as t-butyl product in its own right. For example, t-butyl alcohol alcohol, t-amyl alcohol, methyl benzyl alcohol, cumyl will be produced if t-butyl hydroperoxide is employed alcohol, cyclohexanol, methyl cyclohexanol, isopropyl as the oxidant while methyl benzyl alcohol is obtained alcohol, and the like. using ethylbenzene hydroperoxide. The alcohol prod In one embodiment of the invention, both water and 45 uct can in turn be readily dehydrated to a useful olefin a water-immiscible organic solvent are present such that such as isobutylene or styrene. After separating from a biphasic reaction mixture is formed. The water, for the epoxidation reaction mixture, the recovered or example, may be introduced through the use of an aque ganopnicogen-containing perrhenate catalyst may be ous solution of an organic hydroperoxide such as ter economically re-used in subsequent epoxidations. Simi tiary butyl hydroperoxide as described earlier. Surpris 50 larly, any unreacted olefin or organic hydroperoxide ingly, selectivity to epoxide remains high under these may be separated and recycled. conditions with minimal formation of glycol by-pro From the foregoing description, one skilled in the art ducts despite the presence of the water. This result was can readily ascertain the essential characteristics of this particularly unexpected in view of the teaching in the invention, and, without departing from the spirit and prior art (U.S. Pat. Nos. 4,564,715 and 4,982,021) that 55 scope thereof, can make various changes and modifica perrhenate compounds of the type used herein will tions of the invention to adapt it to various usages, con catalyze the hydrolysis of epoxides to glycols. The ditions, and embodiments. olefin substrate itself and/or the organic hydroperoxide The following examples further illustrate the process may serve as the organic solvent if sufficiently immisci of this invention, but are not limitative of the invention ble with water. Generally, the solvent will be selected 60 in any manner whatsoever. such that the organopnicogen-containing perrhenate catalyst is substantially dissolved in the organic phase of EXAMPLE 1 the reaction mixture in preference to the aqueous phase. Tetrabutyl ammonium perrhenate (n-Bu-N)(ReO4)) The organic solvents described hereinabove, especially was prepared by adding an aqueous solution of tetrabu the aliphatic hydrocarbons, aromatic hydrocarbons, 65 ty ammonium chloride (0.96 g; 3.5 mmole) to an aque halogenated aliphatic hydrocarbons, and halogenated ous solution of potassium perrhenate (1.0 g; 3.5 mmole aromatic hydrocarbons are especially preferred for use. in 50 g boiling water). The white precipitate of tetrabu The amount of water employed in this embodiment of tyl ammonium perrhenate thus obtained was collected 5,118,822 11 12 by filtration, washed several times with water, and vac lene chloride (20g), trans-É-methylstyrene (0.15 g; 1.3 uum dried. mmole), and 3M t-butyl-hydroperoxide in isooctane (0.6 A reaction mixture containing tetrabutyl ammonium g; 2.6 mmole TBHP) was refluxed at 40° C. for 16 perrhenate (0.065 g; 0.13 mmole), methylene chloride hours. Olefin conversion was 72% with 87% selectivity (20g), trans-(3-methyl-styrene (0.15 g; 1.3 mmole), and to trans-(3-methylstyrene oxide (63% yield). 3M t-butyl hydroperoxide in isooctane (0.6 g 2.6 mmole TBHP) was refluxed at 40° C. for 16 hours. Epoxide EXAMPLES 4-1 yield was followed by GC using hexadecane as internal To demonstrate the use of other organic hydroperox standard. Conversion of the olefin substrate was 78% ides and other olefin substrates in the process of this with 85% selectivity to trans-g-methylstyrene oxide; invention, the epoxidation reactions shown in Table 1 the yield of epoxide product was 65%. were performed. One equivalent of olefin, two equiva lents of organic hydroperoxides, 1 mole % tetrabutyl EXAMPLE 2 ammonium perrhenate catalyst, and methylene chloride This example illustrates the use of an aqueous solution solvent were combined and reacted as described in of an organic hydroperoxide in a two-phase reaction Example 1 using the reaction temperatures and times medium in accordance with the process of this inven indicated in the table. Comparative examples 9-11 show tion. A biphasic mixture containing potassium perrhe that hydrogen peroxide cannot successfully be used as a nate (0.01 g), tetrabutyl ammonium chloride (0.01 g), replacement for the organic hydroperoxide in the pro 70% aqueous t-butyl hydroperoxide (0.5 g), trans-g- cess of this invention as little or none of the desired methylstyrene (0.15 g), and methylene chloride (20 g) 20 epoxide is formed. TABLE I Ex. Olefin Hydroperoxide Temp. (C.) Time (hr) Epoxide Epoxide Yield 7% 4 l-octene TBHP 40 18 i-octene oxide <5 5 trans-g-methylstyrene EBHP2 40 16 trans-S-methylstyrene oxide 40 6 cyclohexene TBHP 40 16 cyclohexene oxide <5 7 a-methylstyrene TBHP 40 8 a-methylstyrene oxide 46 8 cis-g-methylstyrene TBHP 40 16 trans-(3-methylstyrene oxide 45 9t 1-octene H2O2 25 62 M O 10' trans-(3-methylstyrene H2O2 25 62 - 03 t cis-g-methylstyrene HO 40 18 - 03 Comparative example -butyl hydroperoxide ethylbenzene hydroperoxide about 20% yield of benzaldehyde was obtained was refluxed at 40° C. for 17 hours. Olefin conversion 35 was 52%, while selectivity to trans-3-methylstyrene EXAMPLES 12-23 oxide was determined to be 88% with negligible forma These examples illustrate the use of various organop tion of hydrolysis by-products. nicogen-containing perrhenate catalysts, organic hy EXAMPLE 3 droperoxides, olefin substrates, and solvents in the 40 epoxidation process of this invention. The epoxidations This example demonstrates the use of an organophos are performed in accordance with the procedure of phonium perrhenate catalyst in the process of this in Example 1 using a 2:1 molar ratio of hydroperoxide:ole vention. fin, 5 mole % (based on olefin) organopnicogen-con Potassium perrhenate (1.0 g; 3.5 mmole) was dis taining perrhenate catalyst, and 75 weight percent solved in 50 g boiling water. An aqueous solution con 45 (based on the total weight of the reaction mixture) of taining tetraphenyl phosphonium chloride (1.31 g; 3.5 the solvent indicated. The epoxidations are carried out mmole) was added with stirring to form a white precipi in standard laboratory glassware where the reaction tate of tetraphenyl phosphonium perrhenate temperature is less than the boiling points of the reac (PhaP)(ReO4)). The precipitate was collected by filtra tants and solvent and in a stainless steel autoclave where tion, washed several time with water, and vacuum 50 the reaction temperature is greater than the boiling dried. point of the most volatile reaction mixture component. A mixture containing the above-prepared tetraphenyl phosphonium perrhenate (0.78 g; 0.13 mmole), methy TABLE II Temp Time Ex. Olefin Catalyst Hydroperoxide Solvent ("C.) (hr) Expected Product 2 vinyl cyclohexane (Me)4AsReO4. TBHPl t-butyl alcohol 50 20 vinyl cyclohexane oxide 13 stilbene Et2Me2NReC4 TAHP2 t-amyl alcohol 80 5 stilbene oxide 4 allyl chloride n-C2H25NH3ReO4. CHP3 cunene 75 3 epichlorohydrin 15 indene PhcH2NMe3ReO4 EBHP4 ethylbenzene 100 O indiene oxide 16 ally alcohol (n-C6H3)2NHReO4. CHHPs cyclohexane 60 12 glycidol 17 methyl oleate n-C6H13PPh3ReO4. TBHP1 toluene 10 15 9,10-epoxy undecanoic acid methyl ester 18 2,3-dimethyl-2-butene 1-hexadecylpyridinium TAHP2 dichloroethane 45 8 2,3-dimethyl-2-butene oxide perrhenate 9 propylene iso-C4H9PPh3ReO4. CHP3 chlorobenzene 100 3 propylene oxide 20 -butene (n-Bu)4AsReO4 EBHP4 benzene 90 6 -butene oxide 2 allyl phenyl ether PhasReO4. CHHP5 mixed hexanes 85 2 phenylglycidyl ether 22 isobutylene Me4SbReO4. TBHP mixed xylenes 65 20 isobutylene oxide 23 norbornene 1-phenethyl-2-picolinium EBHP ethylbenzene 70 8 norbornene oxide 5,118,822 13 14 TABLE II-continued Temp Time Ex. Olefin Catalyst Hydroperoxide Solvent (C.) (ht) Expected Product perrhenate 't-butyl hydroperoxide t-amyl hydroperoxide cumene hydroperoxide 'ethylbenzene hydroperoxide cyclohexane hydroperoxide I claim: 1. A process for epoxidizing an olefin comprising contacting the olefin with an organic hydroperoxide in the presence of an amount of a rhenium catalyst com wherein R, R, R2, and R3 are the same or different and prised of a perrhenate anion and an organopnicogen- 15 are selected from the group consisting of hydrogen, containing cation effective to form an epoxide of the C1-C20 linear, branched, or cyclic alkyl, C6-C20 aryl, olefin. and C7-C20 aralkyl, with the proviso that not all of R, 2. The process of claim 1 wherein the pnicogen of the R, R2, and R3 are hydrogen, and Pn is N, P, or As, organopnicogen-containing cation is N, P, or As. effective to form an epoxide of the olefin. 3. The process of claim 1 wherein the organopnico- 20 7. The process of claim 6 wherein the olefin has the gen-containing cation has the general formula general structure

R14 R16 wherein R, R1, R2 and R3 are the same or different and 25 are selected from the group consisting of hydrogen, R1 R17 C1-C20 linear, branched, or cyclic alkyl, C6-C20 aryl, and C7-C20 aralkyl, with the proviso that not all of R, wherein at least one of R4, R15, R16, or R17 is an aro R, R2, and R3 are hydrogen, and Pn is N, P, or As; or matic substituent and the remaining R substituents are the general formula 30 the same or different and are selected from the group consisting of hydrogen and C1-C8 alkyl. 8. The process of claim 6 wherein the secondary or tertiary organic hydroperoxide is selected from the wherein R, R5, R6, R7, R8, R9, R10 are the same or group consisting of t-butyl hydroperoxide, t-amyl hy different and are selected from the group consisting of 35 droperoxide, cumene hydroperoxide, and ethylbenzene hydrogen, C1-C20 linear, branched, or cyclic alkyl, hydroperoxide. C6-C20 aryl, and C7-C20 aralkyl, with the proviso that 9. The process of claim 6 wherein none of R, R, R2, R7 is not hydrogen, and Pn2 and Pn are the same or or R3 is hydrogen. different and are N, P, or As. 10. The process of claim 6 wherein the molar ratio of 4. The process of claim 1 wherein the olefin is an 40 olefin:organic hydroperoxide is from about 100:1 to alkenyl aromatic compound. 1:100. 5. The process of claim 1 wherein the organic hydro 11. The process of claim 6 wherein the molar ratio of peroxide is a secondary or tertiary hydroperoxide hav olefin:rhenium is from about 10,000:1 to 1:1. ing the general structure 12. The process of claim 6, wherein said contacting is 45 carried out at a temperature of from about 0° C. to 150 Rll C. R12-C-OOH 13. The process of claim 6 wherein said contacting is carried out for a time of from about 10 minutes to 48 his hours. 50 14. The process of claim 6 wherein an organic solvent wherein R, R2, and R13 are the same or different and is additionally present during said contacting. are selected from the group consisting of hydrogen, 15. A process for epoxidizing an olefin comprising methyl, ethyl, and phenyl. contacting the olefin with an organic hydroperoxide in 6. A process for epoxidizing an olefin wherein at least the presence of catalytically effective amounts of an one of the ethylenically unsaturated functional groups 55 alkali metal perrhenate and an organopnicogen halide of the olefin bears an aromatic substituent, said process salt. comprising contacting the olefin with a secondary or 16. The process of claim 15 wherein the alkali metal tertiary hydroperoxide having the general structure perrhenate is lithium perrhenate, sodium perrhenate, or potassium perrhenate. 17. The process of claim 15 wherein the organopnico gen halide salt has the general formula wherein R11, R12, and R13 are the same or different and 65 wherein R, R1, R2, and R3 are the same or different and are selected from the group consisting of hydrogen, are selected from the group consisting of hydrogen, methyl, ethyl, and phenyl in the presence of a rhenium C1-C20 linear, branched, or cyclic alkyl, C6-C20 aryl, catalyst having the general formula and C7-C20 aralkyl, with the proviso that not all of R, 5,118,822 15 16 R, R2, and R3 are hydrogen, Pn is N, P, or As, and X an alkali metal perrhenate and an organopnicogen hal is Cl, Br, or I; or the general formula ide salt. 24. The process of claim 23 wherein the alkali metal perrhenate is lithium perrhenate, sodium perrhenate, or 5 potassium perrhenate. wherein R, R5, R6, R7, R8, R9, and R10 are the same or 25. The process of claim 23 wherein the organopnico different and are selected from the group consisting of gen halide salt has the general formula hydrogen, C1-C20 linear, branched, or cyclic alkyl, C6-C20 aryl, and C7-C20 aralkyl, with the proviso that R7 is not hydrogen, Pn2 and Pnare the same or differ 10 ent and are N, P, or As, and X2 and X3 are the same or wherein R, R, R2, and R3 are the same or different and different and are N, P, or As. are selected from the group consisting of hydrogen, 18. The process of claim 15 wherein an organic sol C1-C20 linear, branched, or cyclic alkyl, C6-C20 aryl, vent is additionally present. and C7-C20 aralkyl, with the proviso that not all of R, 19. The process of claim 15 wherein water is addition 15 R1, R2, and R3 are hydrogen, Pn is N, P, or As, and X ally present. is Cl, Br, or I; or the general formula 20. The process of claim 15 wherein both water and an organic solvent are additionally present. 21. The process of claim 15 wherein the organic hy wherein R4, Ris, R6, R7, R8, R9, and R10 are the same or droperoxide is a secondary or tertiary hydroperoxide 20 different and are selected from the group consisting of having the general structure hydrogen, C1-C20 linear, branched, or cyclic alkyl, C6-C20 aryl, and C7-C20 aralkyl, with the proviso that R7 is not hydrogen, Pn2 and Pn are the same or differ ent and are N, P, or As, and X2 and X are the same or 25 different and are N, P, or As. 26. The process of claim 23 wherein the water-immis cible organic solvent is selected from the group consist wherein R1, R12, and R13 are the same or different and ing of halogenated aliphatic hydrogens, halogenated are selected from the group consisting of hydrogen, aromatic hydrocarbons, aliphatic hydrocarbons, and methyl, ethyl, and phenyl. 30 aromatic hydrocarbons. 22. The process of claim 15 wherein the olefin is an alkenyl aromatic compound. 27. The process of claim 23 wherein the olefin has the 23. A process for epoxidizing an olefin wherein at general structure least one of the ethylenically unsaturated functional groups of the olefin bears an aromatic substituent, said 35 R4 R16 process comprising contacting a secondary or tertiary hydroperoxide having the general structure R R17

Rll wherein at least one of R1, Rl5, R16, or R17 is an aro matic substituent and the remaining R substituents are R12-C-OOH selected from the group consisting of hydrogen and is C1-C8 alkyl. 28. The process of claim 23 wherein R1, R12, R13 are wherein R11, R12, and R13 are the same or different and each methyl. are selected from the group consisting of hydrogen, 45 29. The process of claim 23 wherein the molar ratio of methyl, ethyl, and phenyl with the olefin in a biphasic alkali metal perrhenate:organopnicogen halide salt is reaction mixture containing water, a water-inniscible from 4:1 to 1:4. organic solvent, and catalytically effective amounts of k sk k k k 50

55

65