USOO5210322A United States Patent (19) 11) Patent Number: 5,210,322 King et al. (45) Date of Patent: "May 11, 1993 (54) PROCESSES FOR THE PREPARATION OF (56) References Cited ETHERS U.S. PATENT DOCUMENTS 75) Inventors: Stephen W. King, Scott Depot; Kurt 4,308,402 12/1981 Edwards et al...... 568/68 D. Olson, Cross Lanes, both of W. Va. OTHER PUBLICATIONS 73) Assignee: Union Carbide Chemicals & Plastics March, J., Advanced Organic Chemistry: Reactions, Technology Corporation, Danbury, Mechanisms, and Structure, 1968, pp. 435-436,477-480, Conn. 878-879 and 36. I'l Notice: The portion of the term of this patent Taylor,Tamura, Roger, Y. et al., Tetrahedron Synthesis, 1975,Letters, pp. No.641-642. 8, 1975, pp. subsequent to Mar. 2, 2010 has been 593-596. disclaimed. Witt, H. et al., Angew Chem, 1970, 82, p. 79. (21) Appl. No.: 585,455 Tundo,1565-1571. Pietro et al., Ind. Eng. Chem. Res., 1988, 27, pp. 22 Filed: Sep. 20, 1990 Dow Chemical U.S.A., Experimental Ethylene Car 51 Int. C.5 CO7C 41/00; CO7C 69/96 bonate XAS-1666.00L Product Bulletin (1982), p. 12. Yak 88 a Texaco Chemical Company, TEXACAR(R) Ethylene (52) U.S.C.6,616,568/69,566,625,566,1587.65 ...... 568/579,568/613; and Propylene Carbonates Product Bulletin (1987), p. 568/606; 568/607; 568/608; 568/609;568/610; 24. 568/614; 568/620; 568/621; 568/622; 568/623; Primary Examiner-Paul J. Killos 568/624; 568/659; 568/660,568/661; 568/662; Attorney, Agent, or Firm-R. M. Allen 568/676.568/678,568/679,568/680:56/i75:568/663; 568/664; 568/670; 568/67; 568/675; 57 ABSTRACT 560/186; 562/423; 558/275; 558/277 A process for preparing ethers which comprises con 58) Field of Search ...... 568/579, 678,613, 618, tacting a carboxylated ether with a metal oxide catalyst 568/619, 608, 609, 610, 614, 607, 620, 621, 622, under conditions effective to produce the ether. 623, 624, 659, 660, 661, 662, 683, 664, 670, 673, 675, 676; 558/275,277 65 Claims, No Drawings 5,210,322 2 (because of elimination) and low yields are obtained PROCESSES FOR THE PREPARATION OF with secondary R. ETHERS Other processes have been developed for the produc tion of ethers. U.S. Pat. No. 4,308,402 discloses a pro RELATED APPLICATIONS cess for cleaving a terminal -CH2OH moiety from an The following are related, commonly assigned appli alkoxyalkanol by reacting an alkoxyalkanol at elevated cations, filed on an even date herewith: temperatures in the presence of heterogeneous nickel. U.S. patent application Ser. No. 07/585,561; U.S. The process is believed to involve an initial dehydro patent application Ser. No. 07,585,560; U.S. patent ap genation of an alcohol to afford an aldehyde followed plication Ser. No. abandoned 07/585,563; U.S. patent 10 by decarbonylation to afford a methylated ether com application Ser. No. 07/585,564; U.S. patent application pound. Ser. No. abandoned 07/585,559; U.S. patent application Tamura, Y. et al., Synthesis, 1975, 641-642, relates to Ser. No. 07/585,456; U.S. patent application Ser. No. the preparation of unsymmetrical sulfides by the alkyla 07/585,565; U.S. patent application Ser. No. tion of thiols with alkyl carbonates in the presence of 07/585,555; and U.S. patent application Ser. No. (U.S. 15 sodium ethoxide and ethanol under refluxing condi Pat. No. 5,104,987)07,585,556; all of which are incorpo tions. rated herein by (U.S. Pat. No. 5,164,497) reference. Enichem Synthesis SpA, Dimethyl Carbonate Prod uct Bulletin, p. 10, discloses the reaction of phenols with BRIEF SUMMARY OF THE INVENTION dimethyl carbonate in the presence of a basic catalyst 1. Technical Field 20 such as NaOH, Na2CO3, NaOCH3, tertiary amines or This invention relates to a process for preparing heterocyclic nitrogenous compounds to give methyl ethers which comprises contacting a carboxylated ether ated phenols. Reaction temperatures of at least 140 C. with a metal oxide catalyst under conditions effective to are required. It is stated that the speed of reaction can be produce the ether, accelerated with catalytic quantities of organic and 2. Background of the Invention 25 Decarboxylation, that is, elimination of the -COOH inorganic halides. group as CO2, is a known process. March, J., Advanced Taylor, Roger, Tetrahedron Letters, No. 8, 1975, Organic Chemistry: Reactions, Mechanisms, and Struc 593-596, discloses the thermal decomposition of car ture, 1968, pp. 435-436, 477-480 and 878-879, describes bonates to ethers utilizing a palladium-charcoal catalyst. various decarboxylation reactions. At pages 435-436, it 30 Witt, H. et al., Angew. Chem., 1970, 82,79, describes is stated that aromatic acids can be decarboxylated by the preparation of substituted diphenyl ethers from heating with copper and quinoline. At pages 477-480, it ortho- and para-substituted diphenyl carbonates in the is stated that aliphatic acids which undergo successful presence of small amounts of potassium carbonate and decarboxylation have certain functional groups or dou at a temperature of 180 C.-260' C. ble or triple bonds in the alpha or beta positions such as 35 Tundo, Pietro et al., Ind, Eng, Chem. Res., 1988, 27, malonic acids, alpha-cyano acids, alpha-nitro acids, 1565-1571, describes the reaction of dialkyl carbonates alpha-aryl acids, alpha-keto acids, alpha-trihalo acids, with phenols, thiophenols and mercaptans under gas beta-keto acids, betagamma-olefinic acids and the like. liquid phase-transfer conditions (continuous flow of At pages 878-879, oxidative decarboxylation is de gaseous reactants over a solid bed supporting a liquid scribed in which lead tetraacetate cleaves carboxyl 40 phase-transfer catalyst) to produce the corresponding groups, replacing them with acetoxy groups, which ethers and thioethers. The solid bed consisted of potas may be hydrolyzed to hydroxyl groups. It is stated that sium carbonate coated with 5 weight percent of CAR compounds containing carboxyl groups on adjacent BOWAX(R) poly(oxyethylene)glycol 6000 for one set carbons (succinic acid derivatives) can be bisdecarbox of experiments and alpha-alumina pellets coated with 5 ylated with lead tetraacetate. It is also stated that com 45 weight percent of potassium carbonate and 5 weight pounds containing geminal carboxyl groups (malonic percent of CARBOWAX(R) poly(oxyethylene)glycol acid derivatives) can be bisdecarboxylated with lead 6000 for another set of experiments. Tundo et al. state at tetraacetate, gem-diacetates (acylals) being produced, page 1568, right hand column, lines 33-42, that the which are hydrolyzable to ketones. reaction of alcohols with dialkyl carbonates produces Various processes for the production of ethers are only transesterification. known. A method commonly employed for the prepa Dow Chemical U.S.A., Experimental Ethylene Car ration of ethers is known as the Williamson synthesis. In bonate XAS-1666.00L Product Bulletin (1982), p. 12, the Williamson synthesis, an alkyl halide or substituted describes the preparation of ethylene sulfide from the alkyl halide is reacted with a sodium alkoxide or sodium reaction of ethylene carbonate with potassium thiocya phenoxide to give the ether product. For the prepara 55 nate at a temperature of 100 C. It is stated that 2 tion of aryl methyl ethers, methyl sulfate is frequently oxazolidinones can be prepared from the reaction of used instead of methyl halides. The Williamson synthe aryl or alkyl isocyanates with ethylene carbonate in the sis involves nucleophilic substitution of an alkoxide ion presence of a catalyst. It is also stated that ethylene or phenoxide ion for a halide ion. Aryl halides cannot in carbonate slowly decomposes to ethylene oxide in general be used because of their low reactivity toward 60 quantitative yields at a temperature above 200 C. and nucleophilic substitution. Disadvantages associated that this reaction is accelerated by the presence of cata with the Williamson synthesis include the production of lysts such as inorganic and organic salts. a mole of by-product salt for each mole of ether product Texaco Chemical Company, TEXACAR(R) Ethyl and the use of certain methylating agents such as methyl ene and Propylene Carbonates Product Bulletin (1987), chloride and methyl sulfate which have toxicity and 65 p. 24, discloses the reaction of ethylene carbonate with handling problems. Also, at page 316 of March, J., su glycerine to give glycidol. It is stated that this reaction pra, it is stated that the Williamson reaction, i.e., probably proceeds through the cyclic carbonate ester of RX-OR'31-ROR", is not successful for tertiary R glycerine. It is also stated that ethylene carbonate may 5,210,322 3 4 be reacted with potassium thiocyanate at elevated tem purposes of this invention, Group IIIB metal oxides perature to give ethylene sulfide. embraces the lanthanides and actinides. As used herein, the term "oxide' embraces oxides, hydroxides and/or DISCLOSURE OF THE INVENTION mixtures thereof. Also, as used herein, the term "CO2 This invention relates to a process for preparing synthon' embraces SO2 synthons such as sulfurous ethers which comprises contacting a carboxylated ether acids and sulfurous acid esters. Sulfur analogs of ethers, with a metal oxide catalyst under conditions effective to i.e., thioethers, are also embraced by this invention. produce the ether. This invention also relates to a process for preparing DETAILED DESCRIPTION ethers which comprises contacting an active hydrogen 10 As indicated above, this invention relates to a process containing compound with a CO2 synthon in the pres for preparing ethers which comprises contacting a car ence of a metal oxide catalyst under conditions effective boxylated ether with a metal oxide catalyst under condi to produce the ether. tions effective to produce the ether. This invention further relates to a process for prepar As also indicated above, this invention relates to a ing ethers which comprises (i) contacting an active 15 process for preparing ethers which comprises contact hydrogen-containing compound with a CO2 synthon ing an active hydrogen-containing compound with a under conditions effective to produce a carboxylated CO2 synthon in the presence of metal oxide catalyst ether, and (ii) contacting the carboxylated ether with a under conditions effective to produce the ether. metal oxide catalyst under conditions effective to pro As further indicated above, this invention relates to a duce the ether. 20 process for preparing ethers which comprises (i) con In a preferred embodiment, the processes of this in tacting an active hydrogen-containing compound with vention can provide ether compounds such as ethylene a CO2 synthon under conditions effective to produce a glycol dimethyl ethers resulting from the reaction of carboxylated ether, and (ii) contacting the carboxylated poly(oxyethylene)glycols and dimethyl carbonate with ether with a metal oxide catalyst under conditions effec no by-product salt formation. As indicated above, a 25 tive to produce the ether. disadvantage associated with conventional Williamson When an active hydrogen-containing compound and ether synthesis is by-product salt formation. CO2 synthon are employed as starting materials, it is In another preferred embodiment of this invention, believed that a transesterification reaction followed by a high yields of ether compounds can be obtained utiliz decarboxylation reaction occurs to provide the desired ing secondary alcohols as starting materials. As indi 30 ether product. The exact reaction mechanism is not cated above, a disadvantage associated with conven fully appreciated but what is appreciated is that an ac tional Williamson ether synthesis is the low yields of tive hydrogen-containing compound starting material ether product obtained with secondary alcohol starting and CO2 synthon starting material can be contacted in materials. the presence of a metal oxide catalyst under conditions End-capping of active hydrogen-containing com 35 described herein to provide an ether product. It is also pounds is a further preferred embodiment of this inven appreciated that a carboxylated ether can be contacted tion. Suitable active hydrogen-containing compounds with a metal oxide catalyst under conditions described such as alcohols, glycols, poly(oxyalkylene)glycols herein to provide an ether product. such as CARBOWAX(R) poly(oxyethylene)glycols and Step (i) of certain processes of this invention can in POLYOX(R) poly(oxyethylene)glycols, surfactants general be referred to as a transesterification reaction. such as TERGITOL (R) nonionic surfactants and other Any suitable transesterification catalyst can be em ethylene oxide and/or propylene oxide derivatives, e.g., ployed in step (i). Such transesterification catalysts are UCONGR) fluids and lubricants can be reacted with a known and include, for example, basic metal oxides, suitable CO2 synthon such as dimethyl carbonate or alkoxides and other basic metal salts such as potassium diethyl carbonate in the presence of a metal oxide cata 45 carbonate, sodium titanate and the like. Other suitable lyst under conditions effective to end-cap the active transesterification catalysts include, for example, hydrogen-containing compound. Methyl-capping and Bronsted acids such as sulfuric acid and Lewis acids ethyl-capping preferably afford desired ether products, such as aluminum triisopropoxide. As discussed herein e.g., SELEXOL (R) materials, such as ethylene glycol after in regard to the decarboxylation catalyst, the dimethyl ethers and ethylene glycol diethyl ethers, e.g., SO transesterification catalyst employed in this invention monoethylene glycol dimethyl or diethyl ether, diethyl likewise may also contain support(s), binding agent(s) ene glycol dimethyl or diethyl ether, triethylene glycol or other additives to stabilize or otherwise help in the dimethyl or diethylether, tetraethylene glycol dimethyl manufacture of the catalyst. Both homogeneous and or diethyl ether and polyethylene glycol dimethyl or heterogeneous catalysts can be employed in the step (i) diethyl ethers. 55 reaction. The amount of transesterification catalyst used The ethers produced in accordance with the pro in step (i) is dependent on the particular catalyst em cesses of this invention are useful for a wide variety of ployed and can range from about 0.01 weight percent or applications such as solvents, liquid absorbents, com less to about 10 weight percent or greater of the total plexing agents, phase transfer catalysts, PCB destruc weight of the starting materials. tion, electronics, absorption refrigeration, recovery of 60 Suitable active hydrogen-containing compound start metals, acid extraction, gas absorption, polymerization ing materials which can be employed in the step (i) catalysts, polymer modification, photography, printing, transesterification reaction include any permissible sub pharmaceutical formulations, fuel additives, fragrances, stituted or unsubstituted active hydrogen-containing flavors and the like. organic compound(s). Illustrative active hydrogen-con For purposes of this invention, the chemical elements taining compound starting materials useful in this inven are identified in accordance with the Periodic Table of tion include, for example, substituted and unsubstituted the Elements, CAS version, Handbook of Chemistry alcohols, phenols, carboxylic acids, amines and the like. and Physics, 67th Ed., 1986-87, inside cover. Also, for Preferred active hydrogen-containing compounds in 5,210,322 5 6 clude alcohols and phenols. The molar ratio of active triethylenetetramine, tetraethylenepentamine, pentae hydrogen-containing compound to CO2 synthon is not thylenehexamine, tetramethylenediamine and hexa narrowly critical and can range from about 0.05:1 or methylenediamine. Other amines include aniline, meth less to about 50:1 or greater, preferably from about 0.1:1 ylaniline, toluidine, anisidine, chloroaniline, bromoani to about 10:1. line, nitroaniline, diphenylamines, phenylenediamine, Suitable active hydrogen-containing compounds in benzidine, aminobenzoic acid, sulfanilic acid and sulfa clude substituted and unsubstituted alcohols (mono-, di nilamide. Still other amines include acetanilide, benzani and polyhydric alcohols), phenols, carboxylic acids lide, aceto-toluidide, nitroacetanilide and the like. (mono-, di- and polyacids), and amines (primary and Preferred active hydrogen-containing starting mate secondary). Other suitable active hydrogen-containing 10 rials which can be employed in the step (i) transesterifi compounds include substituted and unsubstituted thio cation reaction include hydroxyl-containing organic phenols, mercaptans, amides and the like. Frequently, compounds such as those embraced by the formula the organic compounds contain 1 carbon to about 100 ROH), wherein R is the residue of an organic com or 150 carbons (in the case of polyol polymers) and can pound and m is a value which satisfies the valencies of contain aliphatic and/or aromatic structures. Most of 15 R, preferably m is a value of from 1 to about 6, more ten, the organic compounds are selected from the group preferably m is a value of from 1 to about 4. Preferred of mono-, di- and trihydric alcohols having 1 to about hydroxyl-containing compound starting materials in 30 carbon atoms. The organic compounds having active clude monohydric, dihydric and polyhydric alcohols. hydrogens can be the product of hydroformylation/hy Illustrative hydroxyl-containing compound starting drogenation reactions. materials useful in this invention include, for example, Suitable alcohols include primary and secondary 2-(2-methoxyethoxy)ethanol, 2-(2-butoxyethoxy)e- monohydric alcohols which are straight or branched thanol, 2-methoxyethanol, alkoxy or allyloxy poly(ox chain such as methanol, ethanol, propanol, pentanol, yalkylene)glycols such as alkoxy or allyloxy CAR hexanol, heptanol, octanol, nonanol, decanol, un BOWAX(R) poly(oxyethylene)glycol materials, ethyl decanol, dodecanol, tridecanol, tetradecanol, pen 25 ene glycol, diethylene glycol, triethylene glycol, tetra tadecanol, hexadecanol, octadecanol, isopropyl alco ethylene glycol, pentaethylene glycol, hexaethylene hol, 2-ethylhexanol, sec-butanol, isobutanol, 2-pentanol, glycol, poly(oxyalkylene)glycols such as CAR 3-pentanol and isodecanol. Particularly suitable alco BOWAX(R) poly(oxyethylene)glycols and PO hols are linear and branched primary alcohols (includ LYOX(R) poly(oxyethylene)glycols, poly(oxye ing mixtures) such as produced by the "Oxo' reaction 30 thylene)(oxypropylene)glycols, phenol, allyl alcohol, of C3 to C20 olefins. The alcohols may also be cycloali diethanolamine, triethanolamine, monoethanolamine, phatic such as cyclopentanol, cyclohexanol, cyclohep surfactants such as TERGITOL (R) nonionic surfactant tanol, cyclooctanol, as well as aromatic substituted materials, alkoxy or allyloxy poly(oxyethylene)(oxy aliphatic alcohols such as benzyl alcohol, phenylethyl propylene)glycols such as UCON (R) lubricant and fluid alcohol, and phenylpropyl alcohol. Other aliphatic 35 materials, 1-methoxy-2-hydroxypropane, 2-propanol, structures include 2-methoxyethanol and the like. cyclohexanol and the like. Phenols include alkylphenols of up to 30 carbons Suitable CO2 synthon starting materials which can be such as p-methylphenol, p-ethylphenol, p-butylphenol, employed in the step (i) transesterification reaction in p-heptylphenol, p-nonylphenol, dinonylphenol and p clude any permissible substituted or unsubstituted car decylphenol. The aromatic radicals may contain other boxyl-containing compound(s) or carbonyl-containing substituents such as halide atoms. compound(s) which are capable of reacting with an Alcohols (polyols) having 2 or more hydroxyl active hydrogen-containing compound under the pro groups, e.g., about two to six hydroxyl groups and have cess conditions described herein, such as those en 2 to 30 carbons, include glycols such as ethylene glycol, braced by the formulae RC(O)R2 or RSOR2 wherein propylene glycol, butylene glycol, pentylene glycol, 45 R1 is hydrogen, halogen, amino, hydroxyl or the residue hexylene glycol, neopentylene glycol, decylene glycol, of an organic compound, and R2 is amino, hydroxyl or diethylene glycol, triethylene glycol and dipropylene the residue of an organic compound. Illustrative CO2 glycol. Other polyols include glycerine, 1,3- synthons include, for example, substituted and unsubsti propanediol, pentaerythritol, galactitol, sorbitol, manni tuted carbonates, chlorocarbonates, carbonic acids, tol, erythritol, trimethylolethane and trimethylolpro SO carbamates, carbamic acids, oxalates, 2-oxazolidinones, pane. ureas, esters, phosgene, chloroformates, carbon dioxide, Carboxylic acids include formic acid, acetic acid, orthocarboxylates, sulfurous acids, sulfurous acid esters propionic acid, butyric acid, valeric acid, caproic acid, and the like. For purposes of this invention, carbon caprylic acid, capric acid, lauric acid, myristic acid, monoxide is also considered a CO2 synthon for appro palmitic acid, stearic acid, oleic acid, linoleic acid and 55 priate oxidative carbonylation reactions. Preferred CO2 linolenic acid. Other carboxylic acids include benzoic synthons include, for example, diethyl carbonate, ethyl acid, cyclohexane carboxylic acid, phenylacetic acid, ene carbonate, dimethyl carbonate, 2-oxazolidinone, toluic acid, chlorobenzoic acid, bromobenzoic acid, ethylene sulfite, phosgene and the like. The use of CO2 nitrobenzoic acid, phthalic acid, isophthalic acid, ter synthons prepared in situ such as the reaction of ethyl ephthalic acid, salicylic acid, hydroxybenzoic acid, ene carbonate and monoethanolamine to give 2 anthranilic acid, aminobenzoic acid, methoxybenzoic oxazolidinone is encompassed within the scope of this acid and the like. invention. Amines include methylamine, dimethylamine, ethyl As indicated above, R1 and R2 can be the residue of anine, diethylamine, n-propylamine, di-n-propylamine, an organic compound. Illustrative residues of organic isopropylamine, n-butylamine, isobutylamine, cyclo 65 compounds include, for example, alkyl, aryl, alkyl hexylamine, piperazine, benzylamine, phenylethyla amino, arylamino, cycloalkyl, heterocycloalkyl, al mine, monoethanolamine, diethanolamine, aminoe kyloxy, aryloxy, cycloalkyloxy, heterocycloalkyloxy, thylethanolamine, ethylenediamine, diethylenetriamine, alkyloxycarbonyl, aryloxycarbonyl, cycloalkyloxycar 5,210,322 7 8 bonyl, heterocycloalkyloxycarbonyl, hydroxycarbonyl tion is not intended to be limited in any manner by the and the like. Additionally, for purposes of defining the step (i) transesterification reaction. CO2 synthon by the formulae above, the R1 and R2 The carboxylated ethers and ethers prepared in ac substituents together can complete a cycloalkyl ring or cordance with this invention can be either symmetrical a heterocycloalkyl ring which can be substituted or or unsymmetrical. For the preparation of carboxylated unsubstituted. The R1CO)R2 formula is also contem ethers and ethers having a symmetrical configuration, it plated to embrace carbon dioxide and carbon monoxide. is preferred to use an alkylene carbonate, e.g., ethylene The step (i) transesterification reaction can be con carbonate or phosgene, as the CO2 synthon starting ducted over a wide range of pressures ranging from material or a molar excess of any active hydrogen-con atmospheric or subatmospheric pressures to superat 10 taining compound starting material with any CO2 syn mospheric pressures. However, the use of very high thon starting material, e.g., a molar ratio of active hy pressures has not been observed to confer any signifi drogen-containing compound to CO2 synthon of from cant advantages but increases equipment costs. Further, about 3:1 to about 10:1. For the preparation of carboxyl it is preferable to conduct the step (i) reaction at re ated ethers and ethers having an unsymmetrical config duced pressures of from about 1 mm Hg to less than 15 uration, it is preferred to use a CO2 synthon starting about 760 mm Hg. The step (i) transesterification reac material other than an alkylene carbonate, e.g., di tion is preferably effected in the liquid or vapor states or methyl carbonate, or an equimolar or molar excess of mixtures thereof. any CO2 synthon starting material with any active hy The temperature of the step (i) transesterification drogen-containing compound starting material, e.g., a reaction may be as low as about ambient temperature to 20 molar ratio of active hydrogen-containing compound to about 300 C. Preferably, the reaction temperature CO2 synthon of from about 0.1:1 to about 1:1. ranges from about 50 C. to about 200 C., and most Step (ii) of certain processes of this invention can in preferably from about 60° C. to about 120° C. general be referred to as a decarboxylation reaction. Suitable carboxylated ethers prepared by the step (i) Suitable decarboxylation catalysts which can be em 25 ployed in step (ii) include one or more metal oxides. A transesterification reaction include any permissible sub magnesium:aluminum mixed metal oxide is a preferred stituted or unsubstituted carboxyl-containing ether metal oxide catalyst as more fully described below. compounds which are capable of eliminating carbon Both homogeneous and heterogeneous catalysts can be dioxide under the Process conditions described herein, employed in the step (ii) reaction. The amount of decar e.g., oxalates, carbonates, carbamates and the like, such 30 boxylation catalyst used in step (ii) is not narrowly as those embraced by the formulae ROC(O)OR1, ROC critical and is dependent on whether step (ii) is con (O)OR2, ROC(O)OC(O)CR1, ROC(O)CC(O)OR2 and ducted batchwise or continuously. If batchwise, the the like wherein R, R and R2 are as defined above. It is catalyst employed can range from about 0.01 weight understood that the R and R1 substituents together and percent or less to about 10 weight percent or greater of the R and R2 substituents together can complete a 35 the total weight of the starting materials. If continu heterocycloalkyl ring which can be substituted or un ously, generally a fixed bed is employed. substituted. Illustrative carboxylated ethers include, for Suitable decarboxylation catalysts for use in the pro example, monoethylene glycol dimethyl or diethyl or cesses of this invention comprise one or more metal diallyl carbonate, diethylene glycol dimethyl or diethyl oxides, preferably mixed metal oxides containing two or or diallyl carbonate, triethylene glycol dimethyl or more metal oxides. Illustrative of such metal oxides diethyl or diallyl carbonate, tetraethylene glycol di include, for example, one or more of the following: methyl or diethyl or diallyl carbonate, polyethylene Group IA metal oxides, Group IIA metal oxides, glycol dimethyl or diethyl or diallyl carbonates, poly Group IIIB metal oxides (including lanthanides and ethylene glycol diisopropyl carbonates, bisglycidyl car actinides), Group IVB metal oxides, Group VB metal bonate and the like. The amount of carboxylated 45 oxides, Group VIB metal oxides, Group VIIB metal ether(s) employed in step (ii) is dependent on the oxides, Group VIII metal oxides, Group IB metal ox amount of metal oxide catalyst employed. ides, Group IIB metal oxides, Group IIIA metal oxides, Illustrative preferred carboxylated ethers include, for Group IVA metal oxides, Group VA metal oxides or example, bis(2-(2-methoxyethoxy)ethyl)-carbonate, Group VIA metal oxides. Certain of these metal oxides bis(2-methoxyethyl)carbonate, bis(2-(2-butoxyethoxy)e- SO may also be used as transesterification catalysts in ac thyl)carbonate, 2-methoxyethyl 2-(2-methoxyethox cordance with this invention such as Group IIA and y)ethyl carbonate, bis(triethylene glycol monomethyl)- IIIA metal oxides. Preferred metal oxides and mixed carbonate, 2-(2-methoxyethoxy)ethyl triethylene glycol metal oxides are amphoteric or basic. Preferred metal monomethyl carbonate, bis(tetraethylene glycol mono oxides which may be utilized as decarboxylation cata methyl)carbonate, triethylene glycol monomethyl tet 55 lysts include, for example, one or more oxides of magne raethylene glycol monomethyl carbonate, bis(2-butox sium, aluminum, calcium, strontium, gallium, beryllium, yethyl)carbonate and the like. barium, scandium, yttrium, lanthanum, cerium, gadolin The carboxylated ethers prepared by the step (i) ium, terbium, dysprosium, holmium, erbium, thulium, transesterification reaction may undergo one or more lutetium, ytterbium, niobium, tantalum, chromium, no transesterifications prior to the step (ii) decarboxylation lybdenum, tungsten, titanium, zirconium, hafnium, va reaction. For example, an active hydrogen-containing nadium, iron, cobalt, nickel, zinc, silver, cadmium, bo compound different from the active hydrogen-contain ron, indium, silicon, germanium, tin, lead, arsenic, anti ing compound starting material may be reacted with the mony and bismuth. originally prepared carboxylated ether under condi Group IIA metal oxides such as magnesium oxide and tions effective to prepare a different carboxylated ether. 65 calcium oxide and Group IIIA metal oxides such as Suitable active hydrogen-containing compounds in aluminum oxide and gallium oxide are preferred mixed clude those embraced by the formula R3OH wherein metal oxides for use in this invention. For mixed metal R3 is the residue of an organic compound. This inven oxides in which at least one of the metals is magnesium, 5,210,322 10 suitable metals in association with magnesium may in provided from metal salts which can either be heated or clude, for example, one or more of the following: precipitated to form the metal oxides. Also, one or more Group IIIA metals such as boron, aluminum, gallium metal oxides may be provided as a partial condensate on and indium, Group IIIB metals such as scandium, yt a support, such as a silica or alpha, beta or gamma alu trium and lanthanum including the lanthanides, Group mina, silicon carbide, and the like, and then condensed VB metals such as niobium and tantalum, Group VIB by heating to effect polymerization to the desired oxide metals such as chromium, molybdenum and tungsten, form. The one or more metal oxides may be condensed Group VIII metals such as iron, cobalt and nickel, from hydrolyzable monomers to the desired oxide(s), Group IIB metals such as zinc and cadmium, Group indeed, to form oxide powders which can thereafter be IVA metals such as silicon, germanium, tin and lead, 10 compressed in the presence of a condensation catalyst Group VA metals such as arsenic, antimony and bis to form pellets and larger structures of the metal oxide muth, and Group IVB metals such as zirconium and decarboxylation catalyst. A blend of the powders and hafnium. For mixed metal oxides in which at least one condensation catalyst can be made into a shapeable of the metals is calcium, suitable metals in association paste which can be extruded and cut into pellets accord with calcium may include, for example, one or more of 15 ing to conventional procedures. The extrudate may the following: Group IIIA metals such as boron, alumi thereafter be fired to cure the condensation catalyst and num, gallium and indium, Group IVA metals such as fix the structure. The cut extrudate may be blended silicon, germanium, tin and lead, Group VB metals such with a support material such as those characterized as niobium and tantalum, and Group VIB metals such as above, and the blend fired to fuse the metal oxide cata chromium, molybdenum and tungsten. 20 lyst to the support. Illustrative of mixed metal oxides which may be used In an embodiment of this invention, a magnesium salt, as decarboxylation catalysts include, for example e.g., magnesium nitrate, and an aluminum salt, e.g., MgO-Al2O3, MgO-SiO2, MgO-CdC), MgO-Bi aluminum nitrate, are precipitated using ammonium 2O3, MgO-Sb2O5, MgO-SnO2, MgO-ZrO2, hydroxide. The material is then washed with deionized MgO-BeO, MgO-TiO2, MgO-CaO, MgO-SrO, 25 water and calcined at a temperature of from about 350 MgO-ZnO, MgO-Ga2O3, MgO-Y2O3, MgO-La C. to about 450° C. to afford the desired magnesium 2O3, MgO-Moo3, MgO-Mn2O3, MgO-Fe2O3, aluminum mixed metal oxide catalyst. MgO-Co3O4, MgO-WO3, MgO-V2O5, MgO-Cr In another embodiment, a magnesium oxide, e.g., 2O3, MgO-ThC2, MgO-Na2O, MgO-BaO, MgO-- magnesium carbonate hydroxide pentahydrate, and an CaO, MgO-HfO2, MgO-Li2O, MgO-Nb2O5, 30 aluminum oxide, e.g., aluminum hydroxide hydrate, are MgO-Ta2O5, MgO-Gd2O3, MgO-Lu2O3, added to deionized water and thoroughly mixed to form MgO-Yb2O3, MgO-CeO2, MgO-Sc2O3, a paste. The paste is then calcined at a temperature of MgO-PbO, MgO-NiO, MgO-CuO, MgO-CoO, from about 350 C. to about 450 C. to afford the desired MgO-B2O3, CaO-SiO2, CaO-Al2O3, CaO-SnO, magnesium:aluminum mixed metal oxide catalyst. CaO-PbO, CaO-Nb2O5, CaO-Ta2O5, CaO-Cr 35 A preferred catalyst structure comprises a Group IIA 2O3, CaO-MoC3, CaO-WO3, CaO-TiO2, CaO-H- and IIIA mixed metal oxide having a surface area of at fO2, MgO-SiO2-Al2O3, MgO-SiO2-ZnO, least about 100 m2/gm which may or may not be MgO-SiO2-ZrO2, MgO-SiO2-CuO, MgO-Si bonded to a support material. The decarboxylation O2-CaO, MgO-SiO2-Fe2O3, MgO-SiO2-B2O3, catalysts on a support preferably have a surface area MgO-SiO2-WO3, MgO-SiO2-Na2O, MgO-Si greater than about 20 m2/gm to as high as about 260 O2-Ga2O3, MgO-SiO2-La2O3, MgO-SiO2-Nb m/gm, or greater depending upon which metal oxides 2O5, MgO-SiO2-Mn2O3, MgO-SiO2-Co3O4, are employed. In the case of magnesium:aluminum ox MgO-SiO2-NiO, MgO-SiO2-PbO, MgO-Si ides, the surface area can be greater than about 50 O2-Bi2O3, MgO-Al2O3-ZnO, MgO-Al2O3-Z- m2/gm to as high as about 260 m/gm, more preferably, rO2, MgO-Al2O3-Fe2O3, MgO-Al2O3-WO3, 45 greater than about 100 m2/gm to as high as about 260 MgO-Al2O3-La2O3, MgO-Al2O3-Co3O4, m/gm, determined according to the single point N2 CaO-SiO2-Al2O3, CaO-SiO2-SnO, CaO-Si method. O2-Nb2O5, CaO-SiO2-WO3, CaO-SiO2-TiO2, The term "support,' as used herein and in the claims, CaO-SiO2-MoO3, CaO-SiO2-HfC)2, CaO-Si means a solid structure which does not adversely affect O2-Ta2O5, CaO-Al2O3-SiO2, CaO-Al2O3-PbO, the catalytic properties of the catalyst and is at least as CaO-Al2O3-Nb2Os, CaO-Al2O3-WO3, CaO-Al stable as the catalyst to the reaction medium. The sup 2O3-TiO2, CaO-Al2O3-MoC)3, CaO-HfO2-Al port can function as a decarboxylation catalyst indepen 2O3, CaO-HfC2-TiO2, and the like. Other suitable dent of the metal oxide catalyst used herein, although it mixed metal oxides embraced within the scope of this may have lower catalytic activity to the reaction. The invention are disclosed by Tanabe et al., Bulletin of the 55 support may act in concert with the catalyst to moder Chemical Society of Japan, Vol. 47(5), pp. 1064-1066 ate the reaction. Some supports may contribute to the (1974). selectivity of the reaction. The catalyst structure can The metal oxides described herein which can be used comprise from about 2 to about 60 percent by weight or as decarboxylation catalysts may contribute to product greater of the support, more preferably from about 10 to selectivity and/or catalytic activity of the reaction and 60 about 50 percent by weight of the support, the remain Mor stability of the catalyst. As discussed hereinafter, ‘der being the weight of the metal oxide(s). Included in the decarboxylation catalyst employed in this invention the weight of the support is the weight of any binding may also contain support(s), binding agent(s) or other agent such as phosphates, sulfates, silicates, fluorides, additives to stabilize or otherwise help in the manufac and the like, and any other additive Provided to stabi ture of the catalyst. lize or otherwise help in the manufacture of the catalyst. The decarboxylation catalysts which comprise one or The support may be Particles as large or larger than the more metal oxides may be prepared in a wide variety of catalyst component and "glued" to the decarboxylation ways. For example, the one or more metal oxides can be catalyst by virtue of a binding medium. 5,210,322 11 12 The support may constitute a separate phase in the are suitable as anion A. Anions suitable for use in combi process of extruding the catalytic structure. In this em nation with the metal cations previously identified as bodiment, the support forming material, preferably as a being particularly suitable are carbonate, halide, phos paste is blended with a Paste of the decarboxylation phate, chromate, sulfate, hydroxide, oxalate, acetate, catalyst or a partial condensate thereof. The paste may nitrate, hexanoate, sebacate, vanadate, molybdate, tung comprise the oxide forms of the support and the decar state and ferrocyanate. boxylation catalyst, each blended with water, and/or binding agents. The extrudate of the blend is passed The foregoing lists of suitable divalent and trivalent through a multiorificed die and chopped into pellets of cations and suitable anions are meant to be illustrative the desired sizes. The particles may be doughnut and not exclusive. Those skilled in the art will recognize shaped, spherical, and the like. Then the particles are O that other cations and anions can be used provided that calcined to dry them and complete any condensation the specific type of cations and their relative amounts reaction in the support and/or the metal oxide decar (x/y ratio) and the specific type of anions and their boxylation catalyst. relative amount result in a mixed metal oxide composi A preferred group of mixed metal oxide catalysts for tion. use in this invention include materials having the for 15 Included in the materials identified above are those mula: based on exchangeable anionic clay minerals. For exam ple, compositions of formula (I) wherein M is magne M2+ Q (OH)2 3y-nzAz" aho () sium and Q is aluminum are related to hydrotalcites, while compositions in which M is nickel and A is alumi wherein M is at least one divalent metal cation; Q is at 20 num are related to takovites. In fact, mixed metal oxides least one trivalent metal cation; and A is at least one prepared using magnesium, nickel or cobalt as the diva anion providing a valence (n), wherein n is at least 1, lent cation and aluminum as the trivalent cation exhibit e.g., between 1 and 4 and most often between 1 and 3, the typical X-ray diffraction pattern of a hydrotalcite. and wherein a is a positive number, M, Q, and A are In a more preferred aspect, the processes of this in provided in a proportion such that x/y is a number 25 vention can utilize mixed metal oxide catalyst composi equal to or greater than 1, Z has a value greater than tions prepared by calcining at an elevated temperature zero and 2x+3y-nz is a positive number. M, Q and A compositions according to formula (). Suitable cal may be selected to provide a layered structure. Prefera cined compositions have the general formula: bly, x/y is in the range of 1 to 12, more preferably x/y is in the range of 1 to 6 and most preferably is in the 30 M’t qt(O)(2+3-)/2D." (II) range of 1 to 4. Preferably, z has a value such that x/z is between n and 12n, more preferably between n and 6n wherein M, Q, x, y, z and n have the same meanings and most preferably between n and 4n. defined above in connection with formula (I), and D is Suitable divalent metal cations, M, broadly include at least one nonvolatile anion. Nonvolatile anions may elements selected from the Transition elements and 35 include, inter alia. halides, nitrates, phosphites, phos Groups IIA and IVA of the Periodic Table as well as phate, vanadate, molybdate, tungstate, sulfite, sulfate, certain Group IIIB elements. As specific examples can chromate, arsenate, borate, chlorate and the like. This be mentioned magnesium, calcium, titanium, vanadium, list is illustrative and not exclusive. chromium, manganese, iron, cobalt, nickel, palladium, platinum, copper, zinc, cadmium, mercury, tin and lead. Heat treating the formula (I) compositions to prepare Divalent metal cations which are particularly suitable the calcined mixed metal oxide compositions of formula are magnesium, nickel, cobalt, zinc, calcium, strontium (II) can be done, for example, at a temperature in the and copper. Suitable trivalent metal cations, Q, broadly range of 200° C. to 800 C. for a period of time of about include elements selected from the Transition elements 12 to 24 hours under an inert atmosphere such as nitro and Groups IIIA and VA of the Periodic Table as well 45 gen or in appropriate cases under an oxidizing atmo as certain Group IIIB elements. As specific examples sphere such as air. can be mentioned aluminum, antimony, titanium, scan Calcination of the mixed metal oxide composition dium, bismuth, vanadium, yttrium, chromium, iron, dehydrates the composition and converts at least par manganese, cobalt, ruthenium, nickel, gold, gallium, tially the metal hydroxides to metal oxides. Any non thallium, and cerium. Trivalent metal cations which are 50 volatile anions may be present in the calcined material. particularly suitable can be selected from aluminum, Provided the calcination temperature is not exces boron, gallium and lanthanum. sive, the mixed metal oxide can be rehydrated to the The composition of formula () also can include a mixed metal hydroxide with water. Generally, the wide range of anions, A. Any anion or combination of mixed metal oxide can be restored readily if the calcina anions which can balance the charge of the cations can 55 tion temperature does not exceed about 600' C. Mixed be used. Suitable anions include inter alia, halides (such metal oxides which are calcined under more severe as chloride, fluoride, bromide, and iodide), nitrite, ni conditions are not easily rehydrated and lower surface trate, sulfite, sulfate, sulfonate, carbonate, chromate, area materials are obtained. cyanate, phosphite, phosphate, molybdocyanate, bicar Certain compositions falling within formula (), such bonate, hydroxide, arsenate, chlorate, ferrocyanide, as hydrotalcite, which comprises a magnesium borate, cyanide, cyanaurate, cyanaurite, ferricyanide, aluminum hydroxide carbonate, and takovite, which selenate, tellurate, bisulfate, as well as organic anions comprises a nickel-aluminum hydroxide carbonate, are such as oxalate, acetate, hexanoate, sebacate, formate, naturally occurring compositions. However, such com benzoate, malonate, lactate, oleate, salicylate, stearate, pounds, as well as their related compositions, also can citrate, tartrate, maleate, and the like. The class of meta 65 be prepared synthetically from inexpensive starting late anions described in U.S. Pat. No. 4,667,045, includ materials using well-known coprecipitation techniques. ing metavanadate, orthovanadate, molybdate, tung Procedures for direct synthesis of such materials are state, hydrogen pyrovanadate and pyrovanadate, also described in Itaya et al., Inorg. Chem. (1987) 5,210,322 13 14 26:624–626; Taylor, R. M., Clay Minerals (1984) or a water soluble salt thereof, or with a water soluble 19:591-603; Reichle, U.S. Pat. No. 4,476,324; Bish, D. salt of tungstic acid or vanadic acid in order to substi L., Bull. Mineral (1980), 103:170-175 and Miyata et al., tute the transition metal anion for the halide anion in the Clays and Clay Minerals (1977), 25:14-18. Using direct catalyst structure thereby to produce a mixed metal synthesis one has the ability to vary within wide limits oxide composition of formula (I). Other ion exchanges the M2/Q3 atomic ratio as well as the anion. will be apparent to those skilled in the art. For example, a composition of formula (I) where Calcined mixed metal oxide compositions may exhibit M2 is nickel or magnesium, Q+3 is aluminum and An a higher level of selectivity/activity than uncalcined is carbonate can be prepared by adding, as aqueous compositions. If a calcined mixed metal oxide catalyst solutions, (a) a mixture of nitrates, sulfates or chlorides 10 composition experiences any decline in selectivity, it of nickel or magnesium and aluminum in a desired can be regenerated by a heat treatment in the presence atomic ratio of nickel or magnesium to aluminum, e.g. 6 of air to restore at least a portion of its initial level of atoms of nickel as nickel chloride to 2 atoms of alumi selectivity/activity enhancement and reused. Condi num as aluminum chloride, to (b) an aqueous solution of tions discussed above for calcining the hydrated mixed a stoichiometric amount of sodium hydroxide and a 15 metal oxide compositions are suitable for regenerating water soluble salt of the desired anion, e.g., sodium compositions which have experienced a decline in ac carbonate. The two solutions are mixed at a tempera tivity. ture of about 25 C. to 35° C. with vigorous stirring Catalysts having the formulas (I) and (II) above over a several-hour period to produce a slurry. The wherein M is at least one of magnesium and calcium, Q slurry then is heated for about 18 hours at a temperature 20 is aluminum or gallium, A is at least one of carbonate, within the range of about 50° C. to 200 C. (preferably bicarbonate, phosphate, sulfate and nitrate, x/y is be between about 60° C. to 75° C) in order to control tween 1 and 20, z has a value which satisfies the rela crystallization and the ultimate particle size of the re tionship: x/z is between n and 12n, and a is a positive sulting crystals. After filtering, and thorough washing number, are generally preferred for vapor phase decar and drying, the solids are recovered, typically as a pow 25 boxylation due to their combination of activity (conver der. sion of precursor) and selectivity. A preferred process As noted above, this procedure can be adapted to a involves a vapor phase process using mixed metal oxide wide variety of cations, cation atomic ratios and anion catalyst wherein M2 is magnesium, Q+ is aluminum, substitutions. For example, water soluble salts of diva A is carbonate, x/y is about 1, and z is about 1. lent magnesium, cobalt, zinc, copper, iron and calcium 30 A group of preferred mixed metal oxide catalyst com can be substituted for the nickel chloride illustrated positions which can be employed in the processes of this above, while water soluble salts of trivalent gallium and invention is disclosed in copending U.S. patent applica lanthanum can replace the aluminum chloride. A wide tion Ser. No. 125,134, filed Nov. 25, 1987, now aban variety of other combinations also will be apparent to doned, the disclosure of which is incorporated herein those skilled in the art. Generally, the rate of metal ion 35 by reference. addition to the aqueous caustic/anion solution is not The step (ii) decarboxylation reaction may be ef critical and can be varied widely. For example, a pre fected in the liquid or vapor or supercritical liquid states ferred preparation method is described in Schaper, H. et or mixtures thereof. In this context, the vapor phase al., Applied Catalysis, 54, 1989, 79-90, the disclosure of reaction is intended to refer to the general vapor state of which is incorporated herein by reference. The reaction 40 the starting materials. Though the step (ii) decarboxyla temperature also is not critical, although the tempera tion reaction conditions may range from subatino ture during the reaction preferably is kept below about spheric or atmospheric to superatmospheric conditions, 100° C. An important feature of the procedure is the use it is desirable to run the step (ii) reaction from about 1 of efficient agitation during the mixing procedure to mm Hg to about 5,000 mm Hg, preferably from about avoid the formation of undesired by-products. 45 100 mm Hg to about 2,500 mm Hg. Loading of an anion A or D into the mixed metal The temperature of the step (ii) decarboxylation reac oxide compositions is influenced by a variety of factors tion may be as low as about 150 C. to about 500 C. including (i) the amount of anion used in the preparation Preferably, the reaction temperature ranges from about relative to the metal cations, (ii) the atomic ratio of the 175' C. to about 375 C., and most preferably from metal cations (x/y) in the preparation procedure, (iii) about 225' C. to about 350 C. the size of the cations and anions and (iv) the prepara Suitable carboxylated ethers for use in the step (ii) tion procedure. As used herein, "loading' is defined as decarboxylation reaction can be prepared by the step (i) the amount of available valences provided by a desired transesterification reaction or by other methods such as anion A or D expressed as a percentage of the total the carbonylation of active hydrogen-containing com available valences for anion A or D. For example, car 55 pounds with carbon monoxide and oxygen at elevated bonate loading in a hydrotalcite-type catalyst can be temperatures in the presence of certain copper salts. maximized by (i) using an excess (e.g., a greater than 3:1 Such a carbonylation process can be an alternative to molar ratio) of sodium carbonate to aluminum chloride the step (i) transesterification reaction and is encom during catalyst preparation and (2) adjusting the atomic passed within the generic scope of this invention. It is ratio of magnesium to aluminum cations to about 2:1. 60 also appreciated that two or more CO2 synthons can be Mixed metal oxide compositions suitable as catalysts reacted under conditions effective to produce a carbox also can be prepared from the native or synthetic hydro ylated ether. talcite-type compositions by ion exchange. For exam The step (ii) decarboxylation reaction can be con ple, hydrotalcite can be treated at ambient conditions ducted in the presence of an inert diluent which can be with 0.01N phosphoric acid for about 18 hours to re 65 either a liquid or gas. When a liquid diluent is employed, place the carbonate anion with phosphate anion. A it should preferably be a good solvent for the starting halide analog of hydrotalcite prepared directly, or by materials, inert under the reaction conditions, and of anion-exchange could be contacted with molybdic acid such a nature that separation from the ether product 5,210,322 15 16 will not be difficult. For instance, the boiling points of ethylene glycol diallyl ethers, methyl-capped and ethyl the diluent and the ether product should differ by an capped polyoxyalkylene materials, cellulose ethers and adequate amount and there should be no tendency of the like. the diluent to form an azeotrope with the desired ether Illustrative of suitable ethers which can be prepared product. by the processes of this invention include those permis Examples of useful liquid diluents that meet the fore sible ethers, including any permissible derivatives of going qualifications include benzene, toluene, xylene, described ethers, which are described in Kirk-Othmer, ethylbenzene, anisole, heptane, octane, nonane, decane, Encyclopedia of Chemical Technology, Third Edition, dibutyl ether, and the like. Hydrocarbons are preferred. 1984, the pertinent portions of which are incorporated Illustrative gaseous diluents include for example, 10 herein by reference. nitrogen, methane, hydrogen, carbon monoxide or car The ether products produced by the processes of this bon dioxide. The gaseous diluent should of course be invention can be separated by distillation. For example, chosen so that it does not prevent the preparation of the a crude reaction product can be subjected to a distilla desired ether products. tion-separation at atmospheric or reduced pressure While the use of such diluents may be beneficial, the 15 through a packed distillation column. Reactive distilla processes of this invention can be operated using pure tion may be useful in conducting the step (i) transesteri starting material(s) as a liquid or gaseous feed. The fication reaction. degree of dilution of the starting materials with various The processes of this invention may be carried out diluents may vary considerably depending upon any using, for example, a fixed bed reactor, a fluid bed reac process constraints restricting the use of the diluent. For 20 tor, or a slurry reactor. The optimum size and shape of example, in commercial production, the use of very the catalyst will depend on the type of reactor used. In large quantities of some gaseous diluents may be disad general, for fluid bed reactors, a small, spherical catalyst vantageous due to the cost of pumping large volumes of particle is preferred for easy fluidization. With fixed bed the gaseous diluent and increased difficulty in isolating reactors, larger catalyst particles are preferred so the the ether product, which increase the energy costs of 25 back pressure within the reactor is kept reasonably low. the process. With liquid diluents, the use of very large The processes of this invention can be conducted in a quantities may be disadvantageous due to the energy batch or continuous fashion, with recycle of uncon cost associated with large recovery and recycle. If the sumed starting materials if required. The reaction can be processes of this invention are to be carried out using a conducted in a single reaction zone or in a plurality of gaseous diluent, in general it is recommended that the 30 reaction zones, in series or in parallel or it may be con starting material(s) constitute from about 1 to about 95, ducted batchwise or continuously in an elongated tubu and preferably about 5 to about 50, mole percent of the lar zone or series of such zones. The materials of con starting material/carrier feed. Increasing the dilution of struction employed should be inert to the starting mate the starting material with a gaseous diluent such as rials during the reaction and the fabrication of the hydrogen may tend to increase the selectivity of the 35 equipment should be able to withstand the reaction reaction to the particular products desired. The amount temperatures and pressures. Means to introduce and/or of liquid diluent can vary widely, for instance, from no adjust the quantity of starting materials or ingredients diluent to about 90 weight percent or greater of the introduced batchwise or continuously into the reaction total weight of the starting materials. zone during the course of the reaction can be conve For processes of this invention in which a carboxyl niently utilized in the processes especially to maintain ated ether is contacted with a metal oxide catalyst under the desired molar ratio of the starting materials. The conditions effective to produce an ether or an active reaction steps may be effected by the incremental addi hydrogen-containing compound and a CO2 synthon are tion of one of the starting materials to the other. Also, contacted in the presence of a metal oxide catalyst the reaction steps can be combined by the joint addition under conditions effective to produce an ether or other of the starting materials to the decarboxylation catalyst. related processes described herein, it is understood that When complete conversion is not desired or not obtain the process conditions described herein for the step (ii) able, the starting materials can be separated from the decarboxylation reaction can desirably be employed for ether product, for example by distillation, and the start such processes. ing materials then recycled back into the reaction zone. The processes of this invention are useful for prepar 50 The processes are conducted for a period of time ing substituted and unsubstituted ethers such as those sufficient to produce the ethers. The exact reaction time embraced by the formulae ROR1 or ROR2 wherein R, employed is dependent, in part, upon factors such as R1 and R2 are as defined above. It is understood that the temperature, nature and proportion of starting materi R and R1 substituents together and the Rand R2 substit als, and the like. The reaction time will normally be uents together can complete a heterocycloalkyl ring 55 within the range of from about one-half to about 100 which can be substituted or unsubstituted. Illustrative hours or more, and preferably from less than about one ethers prepared by the processes of this invention in to about ten hours. clude, for example, dimethyl and diethyl ethers of poly The processes may be conducted in either glass lined, ethylene glycols, e.g., SELEXOL (R) materials, mono stainless steel or similar type reaction equipment. The ethylene glycol dimethyl or diethyl ether (glyme and reaction zone may be fitted with one or more internal ethyl glyme), diethylene glycol dimethyl or diethyl and/or external heat exchanger(s) in order to control ether (diglyme and ethyl diglyme), triethylene glycol undue temperature fluctuations, or to prevent any possi dimethyl or diethyl ether (triglyme and ethyl triglyme), ble "runaway" reaction temperatures. tetraethylene glycol dimethyl or diethyl ether (tetra Illustrative of suitable reactants in effecting the pro glyme and ethyl tetraglyme), polyethylene glycol di 65 cesses of this invention include by way of example: methyl or diethyl ethers (polyglymes and ethyl poly DMC-dimethyl carbonate glymes), bisglycidyl ether, polyethylene glycol diiso DEC-diethyl carbonate propyl ethers, polyethylene glycol dibutyl ethers, poly MCA-2-(2-methoxyethoxy)ethanol 5,210,322 17 18 BCA-2-(2-butoxyethoxy)ethanol MGEE-monoethylene glycol diethyl ether (ethyl MCE-2-methoxyethanol glyme) AA-allyl alcohol DGEE-diethylene glycol diethyl ether (ethyl di EG-ethylene glycol glyme) DEG-diethylene glycol TIGEE-triethylene glycol diethyl ether (ethyl tri TEG-triethylene glycol glyme) TAEG-tetraethylene gylcol TAGEE-tetraethylene glycol diethyl ether (ethyl PAEG-pentaethylene glycol tetraglyme) HEG-hexaethylene glycol PAGEE-pentaethylene glycol diethyl ether (ethyl PEG-CARBOWAX(R)poly(oxyethylene)glycols O pentaglymes) MPEG-alkoxy or allyloxy CARBOWAX(R) HGEE-hexaethylene glycol diethyl ether (ethyl poly(oxyethylene)glycols hexaglymes) MHP-1-methoxy-2-hydroxypropane PGEE-polyethylene glycol diethyl ethers (ethyl IPA-2-propanol polyglynes) PGS-polyethylene glycols 15 PGPE-polyethylene glycol diisopropyl ethers (iso POLX-POLYOX(R) poly(oxyethylene)glycols propyl polyglymes) TER-TERGITOL (R) nonionic surfactants PGBE-polyethylene glycol dibutyl ethers UC-UCON (R) fluids and lubricants PGAE-polyethylene glycol diallyl ethers DEA-diethanolaine DEPE-2-(N,N-dimethyl)ethyl phenyl ether MEA-monoethanolamine 20 OME-n-octyl methyl ether TEA-triethanolamine CME-cyclohexyl methyl ether MGMC-monoethylene glycol dimethyl carbonate BMEE-bis(2-morpholinoethyl)ether DGMC-diethylene glycol dimethyl carbonate CE-cellulose ethers TIGMC-triethylene glycol dimethyl carbonate Illustrative of permissible reactions encompassed TAGMC-tetraethylene glycol dimethyl carbonate 25 within the scope of this invention include, for example, PAGMC-pentaethylene glycol dimethyl carbonate the following reactant/product combinations: HGMC-hexaethylene glycol dimethyl carbonate PGMC-polyethylene glycol dimethyl carbonates BBC-bis(2-butoxyethyl)carbonate REACTANT(S) PRODUCT(S) 30 DMC, MCA TAGME BGC-bisglycidyl carbonate DMC, MCA OGME GLY-glycidol DMC, MCE MGME BE-2-butoxyethanol DMC, AA DAE DAC-diallyl carbonate MHP, DMC DMP EG, DMC MGME MGEC-monoethylene glycol diethyl carbonate 35 DEG, DMC DGME DGEC-diethylene glycol diethyl carbonate TEG, DMC TIGME TIGEC-triethylene glycol diethyl carbonate TAEG, DMC TAGME PAEG, DMC PAGME TAGEC-tetraethylene glycol diethyl carbonate HEG, DMC HGME PAGEC-pentaethylene glycol diethyl carbonate MPEG, DMC PGME HGEC-hexaethylene glycol diethyl carbonate PEG, DMC PGME PGEC-polyethylene glycol diethyl carbonates BE, DMC DCE GLY, DMC BGE PGPC-polyethylene glycol diisopropyl carbonates DAC DAE PGBC-polyethylene glycol dibutyl carbonates MGMC MGME PGAC-polyethylene glycol diallyl carbonates OGMC DGME DEPC-2-(N,N-dimethyl)ethyl phenyl carbonate TGMC TIGME 45 TAGMC TAGME OMC-n-octyl methyl carbonate PAGMC PAGME CMC-cyclohexyl methyl carbonate HGMC HGME BMEC-bis(2-morpholinoethyl)carbonate PGMC PGME CC-cellulose carbonates BGC BGE BBC DGOE Illustrative of suitable products prepared by the pro 50 MGEC MGEE cesses of this invention include by way of example: OGEC DGEE DMP-1,2-dimethoxypropane TGEC TGEE DAE-diallyl ether TAGEC TAGEE PAGEC PAGEE MGME-monoethylene glycol dimethyl ether HGEC HGEE (glyme) 55 PGEC PGEE DGME-diethylene glycol dimethyl ether (diglyme) PGPC PGPE PGBC PGBE TIGME-triethylene glycol dimethyl ether (tri PGAC PGAE glyme) DEPC DEPE TAGME-tetraethylene glycol dimethyl ether (tet OMC OME raglyme) 60 CMC CME PAGME-pentaethylene glycol dimethyl ether (pen BMEC BMEE taglyme) HGME-hexaethylene glycol dimethyl ether (hexa As used herein, the phrase "residue of an organic glyme) compound' is contemplated to include all permissible PGME-polyethylene glycol dimethyl ethers (poly- 65 residues of organic compounds. In a broad aspect, the glymes) permissible residues include acyclic and cyclic, DGDE-diethylene glycol dibutyl ether branched and unbranched, carbocyclic and heterocy BGE-bisglycidyl ether clic, aromatic and nonaromatic residues of organic com 5,210,322 19 20 pounds. Illustrative organic compound residues in cake was then calcined in air at a temperature of 400 C. clude, for example, alkyl, aryl, cycloalkyl, heterocy for a period of 3 hours to afford a magnesium:aluminum cloalkyl, alkyl(oxyalkylene), aryl(oxyalkylene), cy mixed metal oxide. cloalkyl(oxyalkylene), heterocycloalkyl(oxyalkylene), hydroxy(alkyleneoxy) and the like. The permissible EXAMPLES 2-5 residues can be substituted or unsubstituted and the Preparation of Bis(2-butoxyethyl)carbonate same or different for appropriate organic compounds. This invention is not intended to be limited in any man A total of 118.2 grams (1 mole) of 2-butoxyethanol, ner by the permissible residues of organic compounds. 120.1 grams (1.5 moles) of dimethyl carbonate, and 1.0 As used herein, the term "substituted' is contem O gram of potassium carbonate were combined in a 300 plated to include all permissible substituents of organic milliliter round bottom three-neck flask equipped with a compounds. In a broad aspect, the permissible substitu straight distillation head and magnetic stirrer. The flask ents include acyclic and cyclic, branched and un contents were heated to reflux at an initial temperature branched, carbocyclic and heterocyclic, aromatic and of 64 C. at the head and 89 C. in the kettle. A me nonaromatic substituents of organic compounds. Illus 15 thanol/dimethyl carbonate azeotrope was slowly re trative substituents include, for example, alkyl, al moved overhead. A total of 99.5 grams of material was kyloxy, aryl, aryloxy, hydroxy, hydroxyalkyl, amino, removed overhead (64° C.-90' C.) over a period of aminoalkyl, halogen and the like in which the number about 13 hours, after which time the kettle temperature of carbons can range from 1 to about 20 or more, prefer rose to 228 C. After this time, the flask contents were ably from 1 to about 12. The permissible substituents 20 cooled (132.2 grams) and filtered into a 200 milliliter can be one or more and the same or different for appro round bottom flask. The flask contents were then priate organic compounds. This invention is not in placed under vacuum. The desired product was col tended to be limited in any manner by the permissible lected at a temperature of 135° C.-142 C. at 6 mm Hg. substituents of organic compounds. A total of 96.6 grams (73.7 percent yield) of bis(2-butox Certain of the following examples are provided to 25 yethyl)carbonate was obtained at a purity of greater further illustrate the processes of this invention. than 99 percent as analyzed by capillary gas chromatog The following apparatus was used for the preparation raphy on a DB-1701 column. of ethers in Examples 2-13 below. An Appied Test Systems, Inc. Model 3620 Split Test Oven equipped Preparation of Bis(2-butoxyethyl)ether with a preheater (stainless steel incho.d.X2 feet) and Bis(2-butoxyethyl)carbonate prepared above was inch (o.d.) stainless steel reactor tube (8 inch length) 30 passed through a catalyst bed containing 10.8 grams of was packed with catalyst and heated to the desired a magnesium:aluminum mixed metal oxide (3/16 inch reaction temperature using a Honeywell Dial-A-Trol tablets, Mg/Al 3:1) at a reaction temperature indicated temperature controller. The temperatures at the top of in Table A below and at a liquid feed rate of about 0.3 the reactor and the bottom were monitored using a 35 milliliters/minute. The feed was continued for a period digital temperature readout. The liquid feed was added of 1 hour and then analyzed by capillary gas chroma (downflow) to the reactor via a Fluid Metering Inc. tography on a DB-1701 column. The results are given in RP-G20 drive pump equipped with an inch pump Table A. head. The system was maintained under nitrogen, which was introduced prior to the liquid preheater and TABLE A was monitored with a rotometer. The product mixture 40 Preparation of Bis(2-butoxyethyl)ether was collected in a 100 milliliter round bottom flask, Example No. 2 3 4. 5 vented first to a dry ice/acetone trap and then a Fire Process Conditions 225 225 250 300 stone valve, Analysis was performed by capillary gas Temperature, C. Product Composition, chromatography (FID) using a DB-1701 column. 45 area % EXAMPLE 1 2-Butoxyethanol 4.83 2.55 S.23 15.50 Bis(2-butoxyethyl)- 53.93 72.57 52.37 30.98 Preparation of Decarboxylation Catalyst carbonate Bis(2-butoxyethyl)- 37.83 22.07 35.29 38.10 A total of 44.1 grams of magnesium nitrate hexahy ether drate and 66.0 grams of aluminum nitrate nonahydrate 50 were dissolved in 200 milliliters of distilled water to give a first solution. A total of 4.8 grams of ammonium EXAMPLES 6-7 carbonate was dissolved in 200 milliliters of concen trated ammonium hydroxide (28-29 weight percent) to Preparation of Bis(sec-butyl)carbonate give a second solution. About 100 milliliters of distilled 55 Bis(sec-butyl)carbonate was prepared from 2-butanol water was heated in a flask at a temperature of 40 C. and dimethyl carbonate via the following procedure. A and the first and second solutions were combined simul total of 51.88 grams (0.7 mol) of 2-butanol, 64.22 grams taneously with good agitation using a mechanical stir (0.71 mol) of dimethyl carbonate, and 1.0 gram (0.003 rer. The rates of addition of the first and second solu mol) of di-n-butyltin dimethoxide were combined in a tions were adjusted to maintain a pH of 9-10. The total 60 250 milliliter 3-neck flask equipped with a distillation addition took 10 minutes and a final pH of 9.5 was ob head and vigreaux column. The reaction mixture was tained. The contents were stirred at a temperature of refluxed under nitrogen overnight (kettle temperature 40 C. for a period of 40 minutes. The resulting precipi 84 C., head temperature 80 C). With a head tempera tate was filtered and washed (ca. 300 milliliters three to ture of 63 C. (kettle 74 C.), the condensate was taken four times) with water at a temperature of 60° C. until 65 over slowly. A total of 46.2 grams of distillate was the pH of the wash was neutral. The filter cake was collected while maintaining a head temperature of less dried at a temperature of 80 C. overnight. The weight than 73 C. A second distillate fraction of 5.7 grams was of the dried filter cake was about 16 grams. The filter collected at a head temperature of 73'-94 C. At this 5,210,322 21 22 point the relative amount of methyl sec-butyl carbonate to bis(sec-butyl)carbonate was about 2:1. The flask was TABLE C cooled and an additional 14.8 grams (0.2 mol) of 2 Preparation of Diethylene Glycol Dimethyl Ether butanol was added and the reaction mixture heated to 8 9 reflux. The condensate was again taken over slowly at a 5 Process Conditions 250 275 Temperature, C. head temperature less than 74 C. to afford an additional Product Composition, 13.7 grams of distillate. At this point the head tempera area? ture reached 133 C. and the kettle temperature was 2-Methoxyethanol 5.77 7.62 169 C. A small distillate fraction (5.7 grams) was taken Monoethylene glycol 5.27 5.54 overhead followed by a second distillate fraction (53.5 O dimethyl ether grams) which contained bis(sec-butyl)carbonate (head Bis(2-methoxyethyl)- 62.23 63.65 temperature 161° C., kettle temperature 174° C). Anal carbonate ysis by capillary gas chromotography showed 93% Diethylene glycol 23.30 23.8 (area) purity of bis(sec-butyl)carbonate with 7% (area) dimethyl ether methyl sec-butyl carbonate. 5 Preparation of Bis(sec-butyl)ether EXAMPLE 10 Bis(sec-butyl)carbonate was passed through a cata Preparation of Cyclohexyl Methyl Ether lyst bed containing 11.5 grams of a magnesium A mixture of cyclohexanol (1 mole) and dimethyl aluminum mixed metal oxide (3/16 inch tablets, Mg/Al carbonate (3 mole) was passed through 11.5 grams of a 3:1) at a reaction temperature indicated in Table B magnesium:aluminum mixed metal oxide (3/16 inch below and at a liquid feed rate of about 0.3 milliliters/- pellets, Mg/Al 3:1) at a temperature of 250 C. and at a minute. The feed was continued for a period of 1 hour liquid feed rate of 0.32 milliliters/minute. After a period and then analyzed by capillary gas chromatography on of one hour, a total of 31 grams of liquid was collected. a DB-1701 column. The results are given in Table B. 25 Analysis was performed by capillary gas chromatogra TABLE B phy (FID) using a DB-1701 column. The results were Preparation of Bis(sec-butyl)ether (area %) as follows: Example No. 6 7 5.9% methanol Process Conditions 250 275 30 3.0% dimethyl carbonate Temperature, "C. 77.3% cyclohexyl methyl ether Product Composition, 7.1% cyclohexanol. area 2% Bis(sec-butyl)carbonate 4.3 12.46 EXAMPLE 11 Bis(sec-butyl)ether 2.82 19.60 35 Preparation of Diethylene Glycol Diethyl Ether A mixture of 2-(2-ethoxyethoxy)ethanol (1 mole) and EXAMPLES 8-9 diethyl carbonate (3 mole) was passed through 11.5 grams of a magnesium:aluminum mixed metal oxide Preparation of Bis(2-methoxyethyl)carbonate (3/16 inch pellets, Mg/Al 3:1) at a temperature of 225 A total of 76.1 grams (1 mole) of 2-methoxyethanol, 40 C. and at a liquid feed rate of 0.29 milliliters/minute. 67.6 grams (0.75 moles) of dimethyl carbonate, and 0.5 After a period of one hour, a total of 30.2 grams of grams of dibutyltin dimethoxide were combined in a liquid was collected. Analysis was performed by capil 250 milliliter round bottom three-neck flask equipped lary gas chromatography (FID) using a DB-1701 col with a straight distillation head and a magnetic stirrer. umn. The results were (area %) as follows: The flask contents were heated to reflux at an initial 45 19.1% diethyl ether temperature of 73 C. at the head and 102 C. in the 16.0% ethanol kettle. After 7 minutes at reflux, a methanol/dimethyl 14.3% diethyl carbonate carbonate azeotrope was slowly removed overhead. A 41.2% diethylene glycol diethyl ether total of 55.9 grams of material was removed overhead 3.3% tetraethylene glycol diethyl ether. (64 C-88 C.) over a period of about 21 hours after 50 which time the kettle temperature rose to 145 C. After EXAMPLE 1.2 this time, the flask contents were cooled and put under Preparation of n-Decyl Methyl Ether vacuum. The desired product was collected at a tem perature of 97” C-105 C. at 3 mm Hg. A total of 77.98 A mixture of 1-decanol (1 mole) and dimethyl car grams (87.5 percent yield) of bis(2-methoxyethyl)car 55 bonate (3 mole) was passed through 11.5 grams of a bonate was obtained at a purity of greater than 99 per magnesium:aluminum mixed metal oxide (3/16 inch cent as analyzed by capillary gas chromatography on a pellets, Mg/Al 3:1) at a temperature of 250 C. and at a DB-1701 column. liquid feed rate of 0.34 milliliters/minute. After a period of 1.1 hour, a total of 36.5 grams of liquid was collected. Preparation of Diethylene Glycol Dimethyl Ether 60. Analysis was performed by capillary gas chromatogra Bis(2-methoxyethyl)carbonate was passed through a phy (FID) using a DB-1701 column. The results were catalyst bed containing 11.5 grams of a magnesium (area %) as follows: :aluminum mixed metal oxide (3/16 inch tablets, Mg/Al 2.5% methanol 3:1) at a reaction temperature indicated in Table C 0.7% dimethyl carbonate below and at a liquid feed rate of about 0.3 milliliters/- 65 75.6% n-decyl methyl ether minute. The feed was continued for a period of 1 hour 9.0% 1-decanol and analyzed by capillary gas chromography on a DB 2.2% n-decyl methyl carbonate 1701 column. The results are given in Table C. 4.5% bis(n-decyl)ether. 5,210,322 23 24 EXAMPLE 13 Preparation of Diethylene Glycol Dimethyl Ether and Preparation of 1,2-Dimethoxypropane (Propylene Tetraethylene Glycol Dimethyl Ether Glycol Dimethyl Ether) Chunks of magnesium:aluminum mixed metal oxide A mixture of 1-methoxy-2-propanol (1 mole) and 5 (Mg/Al 3:1) materials were crushed to a fine powder dimethyl carbonate (4 mole) was passed through 11.5 and calcined at a temperature of 400° C. overnight. A grams of a magnesium:aluminum mixed metal oxide total of 2.5 grams of the calcined magnesium:aluminum (3/16 inch pellets, Mg/Al 3:1) at a temperature of 250 mixed metal oxide (Mg/Al 3:1) materials was charged C. and at a liquid feed rate of 0.35 milliliters/minute. to a 7.5 inch stainless steel tube (3/8 inch o.d.) which After a period of 1 hour, a total of 30.6 grams of liquid O was then connected to a preheater installed in a Hewlett was collected. Analysis was performed by capillary gas Packard GC oven. The temperature was set at 275 C. chromatography (FID) using a DB-1701 column. The and, after reaching reaction temperature, the methyl results were (area 2%) as follows: 2-(2-methoxyethoxy)-ethyl carbonate prepared above 12.5% methanol (generally 10 grams) was fed via a FMI piston pump at 0.6% dimethyl carbonate 15 0.5 milliliters/minute with a nitrogen sweep. The mate 75.7% propylene glycol dimethyl ether rial at the reactor outlet was allowed to condense in a 8.7%. 1-methoxy-2-propanol. sample bottle (cooled in dry ice/acetone) equipped with an outlet vented to the hood. Products were analyzed EXAMPLES 14-22 on a gas chromatograph and the results are given in Preparation of Methyl 2-(2-Methoxyethoxy)ethyl 20 Table D below. TABLE D Preparation of Digivine and Tetragilvime Example No. 14 15 16 7 18 19 20 21 22 Catalyst Composition 2/1 2/1 3/1 4/1 5/1 3/1 3/3/1 3/3/1 5/1 Mg/A ratio Product Composition, Area 2% Methyl Carbitol 20.50 0.72 0.80 5.95 7.48 21 10.46 8.42 25.05 Dimethyl Carbonate 7.95 0.00 000 2.39 .54 0.46 3.85 4.09 0.00 Methyl 2-(2-methoxyethoxy)- 36.87 0.31 0.42 7.66 0.21 0.36 18.22 9.23 0.22 ethyl carbonate Bis(2-(2-methoxyethoxy)- 9.34 000 000 3.35 000 000 9.80 4.0 0.00 ethyl)carbonate Diethylene glycol 12.13 82.32 82.07 57.17 77.95 84.32 44.28 60.3 7.62 dimethyl ether (Diglyme) Tetraethylene glycol 2.18 14.84 15.07 10.27 2.14 11.54 1.37 11.91 1.94 dimethyl ether (Tetraglyme) 1.03 1.81 1.64 3.21 0.68 2.1 2.02 2.03 1.17 Unknowns Co/Mg/Al "Ni/Mg/Al

Carbonate Although the invention has been illustrated by certain A total of 144.2 grams (1.2 mol) of 2-(2-methoxye of the preceding examples, it is not to be construed as thoxy)ethanol, 400 grams (4.4 mol) of dimethyl carbon- 45 being limited thereby; but rather, the invention encom ate and 3 grams (0.05 mol) of sodium methoxide were passes the generic area as hereinbefore disclosed. Vari combined in a 1-liter 3-neck round bottom flask ous modifications and embodiments can be made with equipped with a 14-inch distillation column, distillation out departing from the spirit and scope thereof. head, and magnetic stirbar. The system was evacuated We claim: and purged three times with nitrogen using a Firestone 50 1. A process for preparing ethers which comprises valve, and left under a constant nitrogen atmosphere. contacting a carboxylated ether with a metal oxide After a period of 1.5 hours at reflux (kettle temperature catalyst under decarboxylation conditions effective to 84 C), methanol (boiling point 64° C) was slowly produce the ether. removed overhead to drive the equilibrium. A total of 2. The process of claim 1 wherein the carboxylated 49.8 grams of methanol was removed over a period of 355 ether comprises a substituted or unsubstituted carboxyl hours, after which time the stopcock was closed and the containing ether compound. reaction mixture was allowed to reflux overnight. The 3. The process of claim 2 wherein the carboxylated mixture was then cooled to room temperature, filtered ether comprises a material having the formulae: and charged (429 grams) to a 500 milliliter round bot tom flask equipped with a distillation head and magnetic ROC(O)OR1 or ROCO)OR2 stirbar. Excess dimethyl carbonate (boiling point 90° C) wherein R is the residue of an organic compound, R1 is was removed overhead. The flask was then cooled, put the residue of an organic compound, and R2 is the resi under vacuum (10-11 mm Hg, and methyl 2-(2-methox due of an organic compound. yethoxy)ethyl carbonate removed overhead (boiling 4. The process of claim 2 wherein the carboxylated point 115-125° C). A total of 193 grams (ca. 90%. 65 yield) was obtained. Gas chromatography analysis of ether comprises a material having the formula: this material showed 97.74% purity (remainder was 2-(2-methoxyethoxy)ethanol). 5,210,322 25 26 wherein R is the residue of an organic compound, R is 19. The process of claim 18 wherein x/y is a number the residue of an organic compound, and R2 is the resi between 1 and 12 and z has a value which satisfies the due of an organic compound. relationship: x/z is between n and 12n. 5. The process of claim 1 wherein the metal oxide 20. The process of claim 18 wherein A is selected catalyst comprises one or more Group IIA metal ox from the group consisting of carbonate, halide, phos ides, Group IIIB metal oxides, Group IVB metal ox phite, phosphate, chromate, sulfate, hydroxide, oxalate, ides, Group VB metal oxides, Group VIB metal oxides, acetate, nitrate, hexanoate, sebacate, vanadate, molyb Group VIIB metal oxides, Group VIII metal oxides, date, tungstate and ferrocyanate. Group IB metal oxides, Group IIB metal oxides, Group 21. The process of claim 18 wherein D is selected IIIA metal oxides, Group IVA metal oxides, Group VA 10 from the group consisting of halides, phosphite, phos metal oxides or Group VIA metal oxides. phate, vanadate, molybdate, tungstate, sulfite, sulfate, 6. The process of claim 5 wherein the metal oxide chromate, arsenate, borate and chlorate. catalyst comprises one or more oxides of magnesium, 22. The process of claim 18 wherein x/y is a number aluminum, calcium, strontium, gallium, beryllium, bar between 1 and 6 and z has a value which satisfies the ium, scandium, yttrium, lanthanum, cerium, gadolin 15 relationship: x/z is between n and 6n. ium, terbium, dysprosium, holmium, erbium, thulium, 23. The process of claim 18 wherein said material lutetium, ytterbium, niobium, tantalum, chromium, mo prepared by calcining the material of formula (I) has lybdenum, tungsten, titanium, zirconium, hafnium, va been heat treated at a temperature in the range of 200 nadium, iron, cobalt, nickel, zinc, silver, cadmium, bo C. to 800 C. for 12 to 24 hours. ron, indium, silicon, germanium, tin, lead, arsenic, anti 20 24. The process of claim 18 wherein M is magnesium mony and bismuth. and and Q is aluminum. 7. The process of claim 1 wherein the metal oxide 25. The process of claim 1 wherein the ether com catalyst comprises at least one Group IIA metal oxide. prises a substituted or unsubstituted ether. 8. The process of claim 1 wherein the metal oxide 26. The process of claim 1 wherein the ether com catalyst comprises a Group IIA metal oxide and a 25 prises a material having the formula: Group IIIA metal oxide. 9. The process of claim 1 wherein the metal oxide ROR catalyst comprises a Group IIA metal oxide and a Group IIIB metal oxide. wherein R is the residue of an organic compound, and 10. The process of claim 1 wherein the metal oxide 30 R1 is the residue of an organic compound. catalyst comprises magnesium oxide and aluminum 27. The process of claim 1 wherein the ether com oxide. prises a material having the formula: 11. The process of claim 1 wherein the metal oxide catalyst comprises a mixed metal oxide. ROR2. 12. The process of claim 1 wherein the metal oxide 35 catalyst has a surface area greater than about 50 m2/gm. wherein R is the residue of an organic compound, and 13. The process of claim 7 wherein the Group IIA R2 is the residue of an organic compound. metal oxide comprises from about 10 weight percent to 28. A process for preparing ethers which comprises about 90 weight percent of the weight of the catalyst. (i) contacting an active hydrogen-containing compound 14. The process of claim 1 wherein the metal oxide 40 with a CO2 synthon under transesterfication conditions catalyst is associated with a support material. effective to produce a carboxylated ether, and (ii) con 15. The process of claim 14 wherein the support com tacting the carboxylated ether with a metal oxide cata prises an alumina material or an alumina-silica material. lyst under decarboxylation conditions effective to pro 16. The process of claim 14 wherein the support com duce the ether. with a metal oxide catalyst under condi 45 tions effective to produce the ether. prises an silica material or a silica-alumina material. 29. The process of claim 28 wherein the active hydro 17. The process of claim 14 wherein the support com gen-containing compound comprises a substituted or prises from about 2 to about 50 percent by weight of the unsubstituted alcohol, phenol, carboxylic acid, amine, metal oxide catalyst. thiophenol, mercaptan or amide. 18. The process of claim 1 wherein the metal oxide 50 30. The process of claim 28 wherein the active hydro catalyst comprises gen-containing compound is selected from the group (a) a material having the formula consisting of substituted and unsubstituted monohydric, Motoh)23-A"...aho (I) dihydric and polyhydric alcohols. 31. The process of claim 30 wherein the hydroxyl wherein M is at least one divalent metal cation; Q is at 55 containing compound comprises 2-(2-methoxyethox least one trivalent metal cation; and A is at least one y)ethanol, 2-(2-butoxyethoxy)-ethanol, 2-methoxye anion providing a valence (n), wherein n is 1 to 4 and thanol, a poly(oxyalkylene) glycol, ethylene glycol, wherein a is a positive number, M, Q and A are pro diethylene glycol, triethylene glycol, tetraethylene gly vided in a proportion such that x/y is a number equal to col, pentaethylene glycol, hexaethylene glycol, a poly or greater than 1, z has a value greater than Zero and 60 (oxyethylene)(oxypropylene)glycol, an alkoxy or al 2x-3y-nz is a positive number, or lyloxy poly(oxyalkylene)glycol, an alkoxy or allyloxy (b) a material prepared by calcining the material of poly(oxyethylene)(oxypropylene)glycol, a polyethyl formula (I) having the formula ene glycol, diethanolamine, triethanolamine, monoetha MQ(O)(2-3- n)/2D" (II) nolamine or 1-methoxy-2-hydroxypropane. 65 32. The process of claim 28 wherein the CO2 synthon wherein M, Q, x, y, z and n have the same meanings comprises a substituted or unsubstituted carbonate, defined above in connection with formula (), and D is chlorocarbonate, carbonic acid, carbamate, carbamic at least one nonvolatile anion. acid, oxalate, 2-oxazolidinone, urea, ester, phosgene, 5,210,322 27 28 chloroformate, carbon dioxide, orthocarboxylate, sulfu 47. The process of claim 45 wherein the active hydro rous acid or sulfurous acid ester. gen-containing compound is selected from the group 33. The process of claim 28 wherein the CO2 synthon consisting of substituted and unsubstituted monohydric, comprises dimethyl carbonate or diethyl carbonate. dihydric and polyhydric alcohols. 34. The process of claim 28 wherein the carboxylated 48. The process of claim 47 wherein active hydrogen ether comprises a substituted or unsubstituted carboxyl containing compound comprises 2-(2-methoxyethox containing ether compound. y)ethanol, 2-(2-butoxyethoxy)-ethanol, 2-methoxye 35. The process of claim 28 wherein the carboxylated thanol, a poly(oxyalkylene)-glycol, ethylene glycol, ether comprises monoethylene glycol dimethyl or di diethylene glycol, triethylene glycol, tetraethylene gly ethyl or diallyl carbonate, diethylene glycol dimethyl or 10 col, pentaethylene glycol, hexaethylene glycol, a poly diethyl or diallyl carbonate, triethylene glycol dimethyl (oxyethylene)(oxypropylene)glycol, an alkoxy or al or diethyl or diallyl carbonate, tetraethylene glycol lyloxy poly(oxyalkylene)glycol, an alkoxy or allyloxy dimethyl or diethyl or diallyl carbonate, a polyethylene poly(oxyethylene)(oxypropylene)glycol, a polyethyl glycol dimethyl or diethyl or diallyl carbonate, bisglyci ene glycol, diethanolamine, triethanolamine, monoetha dyl carbonate, a polyethylene glycol diisopropyl car 15 nolamine or 1-methoxy-2-hydroxypropane. bonate or a polyethylene glycol dibutyl carbonate. 49. The process of claim 45 wherein the CO2 synthon 36. The process of claim 28 wherein the metal oxide, comprises a substituted or unsubstituted carbonate, catalyst comprises one or more Group IA metal oxides, chlorocarbonate, carbonic acid, carbamate, carbamic Group IIA metal oxides, Group IIIB metal oxides, acid, oxalate, 2-oxazolidinone, urea, ester, phosgene, Group IVB metal oxides, Group VB metal oxides, 20 choroformate, carbon dioxide, orthocarboxylate, sulfu Group VIB metal oxides, Group VIIB metal oxides, rous acid or sulfurous acid ester. Group VIII metal oxides, Group IB metal oxides, 50. The process of claim 45 wherein the CO2 synthon Group IIB metal oxides, Group IIIA metal oxides, comprises dimethyl carbonate or diethyl carbonate. Group IVA metal oxides, Group VA metal oxides or 51. The process of claim 45 wherein the metal oxide 25 catalyst comprises one or more Group IA metal oxides, Group VIA metal oxides. Group IIA metal oxides, Group IIIB metal oxides, 37. The process of claim 36 wherein the metal oxide Group IVB metal oxides, Group VB metal oxides, catalyst comprises one or more oxides of magnesium, Group VIB metal oxides, Group VIIB metal oxides, aluminum, calcium, strontium, gallium, beryllium, bar Group VIII metal oxides, Group IB metal oxides, ium, scandium, yttrium, lanthanum, cerium, gadolin 30 Group IIB metal oxides, Group IIIA metal oxides, ium, terbium, dysprosium, holmium, erbium, thulium, Group IVA metal oxides, Group VA metal oxides or lutetium, ytterbium, niobium, tantalum, chromium, mo Group VIA metal oxides. lybdenum, tungsten, titanium, zirconium, hafnium, va 52. The process of claim 51 wherein the metal oxide nadium, iron, cobalt, nickel, zinc, silver, cadmium, bo catalyst comprises one or more oxides of magnesium, ron, indium, silicon, germanium, tin, lead, arsenic, anti 35 aluminum, calcium, strontium, gallium, beryllium, bar mony and bismuth. ium, scandium, yttrium, lanthanum, cerium, gadolin 38. The process of claim 28 wherein the metal oxide ium, terbium, dysprosium, holmium, erbium, thulium, catalyst comprises at least one Group IIA metal oxide. lutetium, ytterbium, niobium, tantalum, chromium, mo 39. The process of claim 28 wherein the metal oxide lybdenum, tungsten, titanium, zirconium, hafnium, va catalyst comprises a Group IIA metal oxide and a nadium, iron, cobalt, nickel, zinc, silver, cadmium, bo Group IIIA metal oxide. ron, indium, silicon, germanium, tin, lead, arsenic, anti 40. The process of claim 28 wherein the metal oxide mony and bismuth. catalyst comprises a Group IIA metal oxide and a 53. The process of claim 45 wherein the metal oxide Group IIIB metal oxide. catalyst comprises at least one Group IIA metal oxide. 41. The process of claim 28 wherein the metal oxide 45 54. The process of claim 45 wherein the metal oxide catalyst comprises magensium oxide and aluminum catalyst comprises a Group IIA metal oxide and a oxide. Group IIIA metal oxide. 42. The process of claim 28 wherein the metal oxide 55. The process of claim 45 wherein the metal oxide catalyst comprises mixed metal oxide. catalyst comprises a Group IIA metal oxide and a 43. The process of claim 28 wherein the ether com Group IIIB metal oxide. prises a substituted or unsubstituted ether. 56. The process of claim 45 wherein the metal oxide 44. The process of claim 28 wherein the ether com catalyst comprises magnesium oxide and aluminum prises monoethylene glycol dimethyl or diethyl ether, oxide. diethylene glycol dimethyl or diethyl ether, triethylene 57. The process of claim 45 wherein the metal oxide glycol dimethyl or diethyl ether, tetraethylene glycol 55 catalyst comprises a mixed metal oxide. dimethyl or diethyl ether, a polyethylene glycol di 58. The process of claim 45 wherein the ether com methyl or diethyl ether, bisglycidyl ether, a polyethyl prises a substituted or unsubstituted ether. ene glycol diisopropyl ether, a polyethylene glycol 59. The process of claim 45 wherein the ether com dibutyl ether or a polyethylene glycol diallyl ether. prises monoethylene glycol dimethyl or diethyl ether, 45. A process for preparing ethers which comprises diethylene glycol dimethyl or diethyl ether, triethylene contacting an active hydrogen-containing compound glycol dimethyl or diethyl ether, tetraethylene glycol with a CO2 synthon in the presence of a metal oxide dimethyl or diethyl ether, a polyethylene glycol di catalyst under decarboxylation conditions effective to methyl or diethyl ether, bisglycidyl ether, a polyethyl produce the ether. ene glycol diisopropyl ether, a polyethylene glycol 46. The process of claim 45 wherein the active hydro 65 dibutyl ether or a polyethylene glycol diallyl ether. gen-containing compound comprises a substituted or 60. The process of claim 1 wherein said decarboxyla unsubstituted alcohol, phenol, carboxylic acid, amine, tion is carried out at a temperature from about 150° C. thiophenol, mercaptain or amide. to about 500 C. 5,210,322 29 30 61. The process of claim 28 wherein said transesterifi lation is carried out at a temperature from about 150 C. to about 500 C. cation is carried out at a temperature from about ambi 64. The process of claim 29 wherein the active hydro ent to about 300° C. gen-containing compound comprises an alcohol having 62. The process of claim 28 wherein said decarboxy about two to six hydroxyl groups. 65. The process of claim 46 wherein the active hydro lation is carried out at a temperature from about 150° C. gen-containing compound comprises an alcohol having to about 500 C. about two to six hydroxyl groups, 63. The process of claim 45 wherein said decarboxy s O

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