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United States Patent (19) 11) Patent Number: 5,047,582 Brotherton Et Al

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United States Patent (19) 11) Patent Number: 5,047,582 Brotherton Et Al United States Patent (19) 11) Patent Number: 5,047,582 Brotherton et al. (45) Date of Patent: Sep. 10, 1991 (54) PROCESS FOR THE OXIDATION OF A TETRAHYDROPHTHALIC ACID 75 Inventors: David L. Brotherton; Kwok W. Fung, COOH both of Easley, S.C. 73) Assignee: Ortec, Inc., Easley, S.C. COOH (21) Appl. No.: 415,890 R 22 Filed: Oct. 2, 1989 51) Int. Cl. ............................................ CO7C 51/285 wherein R and R' independently are H, alkyl, aryl or 52 U.S. Cl. .................................... 562/508; 560/125; halo, to a glycol of the formula 560/126; 560/190; 562/507; 562/509; 562/525; 562/590 R 58) Field of Search ............... 562/469, 508, 509, 525, HO COOH 562/590, 507; 560/125, 126, 190 (56) References Cited HO COOH U.S. PATENT DOCUMENTS R" 2,203,628 6/1940 Hopff et al. ......................... 562/524 3,284,492 l 1/1966 Fremery et al. .................... 562/48 3,535,367 10/1970 Inoue et al. ......................... 560/26 comprises treating the tetrahydro compound with hy 3,915,997 0/1975 Ladd ............................... 562/523 X drogen peroxide at an elevated temperature in the ab 4,305,824 12/1981 Uemura et al. ................ 20/500.29 sence of a catalyst. 4,331,608 5/1982 Kawamoto et al. ................ 260/406 The thus-formed glycol can be further oxidized in a 4,391,945 5/1983 Mashio et al. ...................... 524/6OO butanetetracarboxylic acid of the formula 4,532,079 7/1985 Venturello et al. ... ... 260/413 4,820,307 4/1989 Welch et al. ............................ 8/20 4,833,272 5/1989 Nakazawa et al. ................. 562/523 RCHCOOH OTHER PUBLICATIONS CHCOOH Venturello et al., J. Org. Chen., vol. 51 (1986), pp. CHCOOH 1599-601. RCHCOOH Franz et al., Chem. and Ind (2/25/61), pp. 250-251. Franz et al., J. Org. Chem., vol. 30 (1965), pp. with hydrogen peroxide in the presence of a catalyst 1488-1491. selected from the group consisting of a manganese salt, Primary Examiner-Jose G. Dees an iron salt, a chromium salt, a cerium salt, a persulfate, Assistant Examiner-Vera C. Clarke a perborate, a silicate, tungstic acid or an ammonium or Attorney, Agent, or Firm-Cort Flint alkali metal salt or heteropolyacid thereof, or molybdic acid or an ammonium or alkali metal Salt or 57 ABSTRACT heteropolyacid thereof. A process for oxidation of a tetrahydro compound of the formula 20 Claims, 4 Drawing Sheets U.S. Patent Sep. 10, 1991 Sheet 2 of 4 5,047,582 Fig.2 SODIUMTUNGSTATE CATALYZED OXDATION (12 Hours, 25 min.) CH2COOH HCOOH CHCOOH CH2COOH PEAK TIME 1.32 2 148 3 2.03 4 3.30 5 3.88 6 6.33 ---- 1.32 3.88 6.33 TIME (min) U.S. Patent Sep. 10, 1991 Sheet 3 of 4 5,047,582 Fig.3a Fig. 3b PRIOR ART EXAMPLE 4 Na2 WO4CATALYST PEAK TIME PEAKTIME 1 4 1 143 2 2.84 2 2.85 3 337 3 337 4 5.4 4 5.6 5 794 143 537 4, 33754 2.85 5.6 2.84 TIME (min) TIME (min) U.S. Patent Sep. 10, 1991 Sheet 4 of 4 5,047,582 Fig. 4d Fig.4b PRIOR ART EXAMPLE 5 PHOSPHOTUNGSTIC ACID CATALYST PEAK TIME 42 2 3.05 3 3.52 PEAK TIME 4 5.8 1 40 5 7.2 2 337 6 9.68 3 5.85 3.05 TIME (min) TIME (min) 5,047,582 1. 2 hydrogen peroxide in the presence of a metal-contain PROCESS FOR THE OXIDATION OF A ing catalyst. Advantages of the process include better TETRAHYDROPHTHALIC ACID control over an exothermic process, than heretofore, and production of a cleaner reaction product. DESCRIPTION DISCLOSURE OF INVENTION 1. Technical Field This invention relates to a process for the non In one aspect, this invention relates to a process for catalytic oxidation of tetrahydrophthalic acids with oxidation of a tetrahydro compound of the formula hydrogen peroxide to 4,5-dihydroxyhexahydrophthalic 10 acids. Further catalytic oxidation of the intermediate R 4,5-dihydroxyhexahydro compounds with hydrogen peroxide yields butane-1,2,3,4-tetracarboxylic acids. COOH Butanetetracarboxylic acids are used in the prepara tion of cellulosic reverse osmosis membranes, as pro COOH posed by Uemura et al. (U.S. Pat. No. 4,305,824); for 15 chelate resins, as proposed by Mashio et al. (U.S. Pat. R" No. 4,391,945) and for durable-press finishing of cotton textiles, as proposed by Welch et al. (U.S. Pat. No. 4,820,307). It is, therefore, apparent that improved R 20 methods for synthesizing butanetetracarboxylic acids COOH are of interest. 2. Background Art Nakazawa et al. (U.S. Pat. No. 4,833,272), herein incorporated by reference, have proposed a process for COOH preparing polycarboxylic acids by subjecting a Diel 25 R" sAlder adduct of maleic anhydride and a diene to oxida tion with hydrogen peroxide in the presence of a cata wherein R and R', are independently H, alkyl, aryl or lyst selected from tungstic acid, molybdic acid or halo, to a glycol of the formula heteropolyacids thereof. Venturello et al. (U.S. Pat. No. 4,543,079) have pro 30 R posed oxidative cleavage of olefins or vicinal dihydroxy compounds by treatment with hydrogen peroxide in a HO COOH biphasic aqueous liquid/organic liquid, in the presence of a catalyst. Catalysts include tungsten quaternary HO COOH ammonium, phosphonium, arsonium or stibonium com 35 pounds. A mechanism for the reaction is presented by R Venturello et al., J. Org. Chem., vol. 51 (1986), pages 1599-1601. comprising treating the tetrahydro compound with Fremery et al., in U.S. Pat. No. 3,284,492, have pro hydrogen peroxide at an elevated temperature in the posed preparing carboxylic acids by ozonization of 40 absence of a catalyst. - - - olefinic bonds in an emulsion containing hydrogen per In another aspect, the invention relates to a process oxide. for further oxidation of the thus-formed glycol to a Kawamoto et al. (U.S. Pat. No. 4,331,608) have re butanetetracarboxylic acid of the formula cited a liquid phase catalytic process for co-oxidizing unsaturated compounds, including unsaturated alicyclic 45 RCHCOOH compounds, in which oxygen and an aldehyde are pres ent, along with a ruthenium catalyst. CHCOOH Inoue et al. (U.S. Pat. No. 3,535,367) have recited a CHCOOH process for preparing 4-hydroxycyclohexanecarboxylic R"CHCOOH acids by treating a cyclohexenecarboxylic acid with 50 sulfuric acid and hydrolyzing a resulting intermediate. The oxidation of tetrahydrophthalic acid or anhy with hydrogen peroxide in the presence of a catalyst dride to butanetetracarboxylic acid, with nitric acid, selected from the group consisting of a manganese salt, generally in the presnece of a vanadium catalyst, has an iron salt, a chromium salt, a cerium salt, a perborate, been investigated by: 55 a persulfate, a silicate, tungstic acid or an ammonium or Hopff et al., U.S. Pat. No. 2,203,628 alkali metal salt or heteropolyacid thereof, or molybdic Ladd, U.S. Pat. No. 3,915,997 acid or an ammonium or alkali metal salt or Johnson, GB Patent 510,638 heteropolyacid thereof. Franz et al., Chem. and Ind., (London), Feb. 25, 1961, DETAILED DESCRIPTION pages 250-251 Franz et al., J. Org. Chem., vol. 30 (1965), pages The starting materials used to prepare cyclic vicinal 1488-1491. glycol intermediates of this invention are Diels-Alder It is an object of this invention to provide a two-step adducts of maleic acid, maleic anhydride, or fumaric process for the preparation of butanetetracarboxylic acid and a 1,3-diene. The diene may be unsubstituted or acids, in which a tetrahydrophthalic acid is oxidized 65 may be substituted in the i- and/or 4-positions. The l with aqueous hydrogen peroxide to a corresponding or 4-substituent may be selected from alkyl, aryl or halo 4,5-dihydroxyhexahydrophthalic compound, which is substituents, of which methyl, ethyl, butyl, hexyl, 2 further oxidized to a butanetetracarboxylic acid with ethylhexyl, dodecyl, isostearyl, phenyl, tolyl, chloro 5,047,582 3 4. phenyl, alpha- or beta-naphthyl, chloro-, bromo- and rates, persulfates, silicates, tungstic acid or an ammo iodo- are representative. The substituents represented nium or alkali metal salt or heteropolyacid thereof, or by R and R' are therefore selected from alkyl of 1-18 molybdic acid or an ammonium or alkali metal salt or carbon atoms, mono- or bicyclic-aryl of up to 10 car heteropolyacid thereof. bon atoms or halo. When the desired product from Manganese salts include, but are not limited to the further oxidation of the intermediate glycol is butanetet chloride, bromide, iodide, nitrate, sulfate, acetate, ben racarboxylic acid, the adduct from butadiene-1,3 zoate or oxalate as well as Salts of higher oxidation (R=R's H) will be employed. states, including potassium permanaganate. Preferably It will be understood that maleic acid, maleic anhy the manganese salt is a salt of Mn(II), of which manga dride and fumaric acid include substituted derivatives, 10 nous chloride is particularly preferred. such as methylmaleic acid. Iron salts include, but are not limited to, ferrous or The non-catalytic oxidation of a tetrahydrophthalic ferric chloride, bromide, iodide, nitate, sulfate, oxalate, acid or anhydride is carried out with aqueous hydrogen acetate, etc. Preferably, the iron salt is of Fe(II), of peroxide at an elevated temperature. When a tetrahy which ferrous sulfate is most preferred. drophthalic anhydride is the starting material, it is pre 15 ferred to first hydrolyze the anhydride to a correspond Tungstic acid means “WO3' or "H2WO4'. A pre ing phthalic acid by heating with water at an elevated ferred salt catalyst is sodium tungstate, which is repre temperature.
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