SU691443A1 - Method of preparing tetraalkyl esters of substituted butane-1,2,3,4-tetracarboxylic acids - Google Patents

Description

NOY with respect to the action of oxidants is an acyloxyalkyl group. The aim of the invention is the development of a new simple and effective method for preparing the tetraalkyl esters of the substituted butan-1u2, 3,4-tetracarboxylic acids not described in the literature and previously unavailable. The goal is achieved by the described method of producing tetraalkyl esters of substituted butane-1,2, 3,4-tetracarboxylic acids, in that the corresponding carboxylic alkyl ester, where alkyl is ethyl or hexyl, is reacted with dimethyl or diethyl maleate in the presence of 10 -20 mol% organic peroxide initiator, such as greb butyl peroxide, at a temperature of 145-ISO C. 5-10-fold molar excess of alkyl ester of carboxylic acid relative to dimethyl-. and diethylemaleate eliminates the side oligomerization process. A distinctive feature of the method is the interaction of the corresponding carboxylic acid alkyl ester, taken 5–10-fold by mole, with dimethyl or diethyl maleate in the presence of an organic cross-initiator in an amount of 10-20 % mol. from maleic ester at 145-180 ° C. As an initiator, it is desirable to substitute g / 7et-butyl peroxide or 7-et-butyl-percetate peroxide. The structure and. The high degree of pure TC compounds, confirm the PMR spectra, the data of the elements of this analysis and. determination of molecular weight (ebullioscopy method). Thus, the structure of 2- (acetoxyhexyl) -butane-1 tetramethyl ester, 2,3,4-tetracarbonic acid CH3COOCH (CyN,) CH (CoHCN) CH (COOCH CIi (COOGH3) CHNCOOSHZ) confirms the presence of the heart of margins. protons from the groups ppm), CHjCOO (2 ppm), CHjCoo, Cencio (2.7 ppm) and SNdo (3.6 ppm) with the ratio of intensities corresponding to the number of corresponding protons in specified broadcast. The found elemental composition and molecular weight of this ester coincide well (within the accuracy of the methods used) with calculated values, indicating a high degree of ester strength, Tetraalkyl esters of unsubstituted butane-1,2,3,4-tetracarboxylic acid, Those closest to the claimed compounds are: tetramethyl ether - viscous. oil with m. bale, 178-183 / 1 mm, tetraethyl ether - solid c. mp, 73-74 ° C, tetrabutyl ether, viscous oil with m. bale. 210-211 / 1 - 2 mm. Lower liquid esters are used as plasticizers, and higher ones as lubricating oils. In addition, on their basis, hardeners of epoxy resins, films, fibers, adhesive insulating materials, and other valuable organic products are obtained. The proposed compounds are very similar in structure to the tetraalkyl esters of n-substituted butane-1, 2,3,4-tetracarboxylic acid. Plasticizing and lubricating properties of these esters, like most of the known plasticizers and lubricants, give ester groups. There are four such groups in these esters and thanks to them these esters have a low volatility and a consistency of viscous oil - the most important qualities that plasticizers and lubricants must have. There are five to six ether groups in the above compounds. In addition, these compounds have a more asymmetrically constructed structure, which, as a rule, reduces the freezing point of organic products. This gives reason to expect that the plasticizing and lubricating properties of these compounds will be even better. . . . Fabricated on the basis of unsubstituted butantetratetracarboxylic acid from hardeners of epoxy resins, films and fibers are obtained by the interaction of this acid, its esters or anhydride with diamines, such as ethylene diamine and tetramethylene diamine, a. adhesives and electrically insulating materials are their sequential c. interaction with amino alcohols and esters of polybasic acids. The ability to form the aforementioned products of unnoticed butantetratetracarboxylic acid, its esters and anhydride is given, respectively, by the adjacent carboxyl, carboalkoxy and anhydride groups, the acyloxy groups have no similar property, which makes it possible to expect for the claimed compounds approximately the same ability to form these products as for Esters of Unsubstituted butane tetracarboxylic acid. The structure of the compounds obtained was confirmed by PMR spectra. Example 1 Preparation of 2- (acetoxyhexyl) -butane-1, 2,3, 4-tetracarbonic acid tetramethyl ester, To 100 g (0.7 mol) of boiling () hexyl acetate, a solution of 2 is added over 4 hours with stirring g (0.014 mol) peroxide of t / z-butyl in 10 g (0.07 mol) of dimethyl maleate. The mixture is heated at a temperature of 170 ° C for another 2 hours, the excess hexacyl acetate is distilled off in vacuum, as well as the reaction products, which have a bale, to 200/15 mm. The residue gives 11.2 g (75%) of tetramethyl ether 2 - (acetoxyhexyl) -butane-1, 2,3,4-tetrakaboxylic acid ..; Found,%: C 56.00; And 7.51; weight 456)

C20

Calculated,%: C 55.55; H 7.41; weight 432.

PRI mme R 2. Preparation of 2- (benzoyl-oxyethyl) -buty-1-l, 2,3,4-tetracarboxylic acid tetraethyl ester.

A solution of 4.1 g (0.024 mol) of tert-butyl peroacetate in 30 g of ethyl benoate was added in 4 hours to a mixture of 200 g (1.3 mol) of ethylbenzoate and 20 g (0.12 mol) of diethyl maleate. The mixture is heated at a temperature of 2 more hours and further, as in Example 1, .22.5 g (77%) of 2- (Benz6yloxyethyl) -buthan-l, 2,3,4-Fetracarbonic acid TI are obtained.

Found,%: C 60.60; H 6.91; . weight 468}

25 34lO

Calculated,% C 60.50; H 6.85; weight 494.

Example 3. Preparation of 2- (ethyloxyaloxyethyl) -butane-1,2,3,4-tetracarboxylic acid tetramethyl ester.

To a boiling mixture () of 100 g (0.7 mol) of oxalic acid diethyl ester and 10 g (0.07 mol) of dimethyl maleate, a solution of 2 g (0.014 mol) of treg-butyl peroxide in 20 g of diethyl oxalate is added in 4 hours. Mixture boiling at a temperature of another 2 hours and further as in Example 1, obtaining: 10.6 g (70%) of tetramethyl ester of 2- (ethyloxyaloxyethyl) -butyl-1,2,3,4-tetracarboxylic acid. : Example 4. Preparation of 2- (benzoyloxyethyl) -butane-1, 2,3,4-tetracarbonic acid tetra-tetyl ester ..

Analogously to example 2, 115 g (0.7 mol) of ethyl benzoate and 20 g (0.12 mol) of diethyl maleate (5-fold excess of ethyl benzoate) when initiating the reaction of 2 g (0.014 mol) of tert-butyl peroxide receive 24 g (82% ) 2- (benzoyloxyethyl) -butane-1,2, 3, 4-tetracarboxylic acid tetraethyl ester.

Found,%: C 59.90; H 6.65,

Example 5. Obtaining tetraethyl ester of 2- (benzoyl oxyethyl) -butan-l, 2, 3, 4-tetracarboxylic acid.

Analogously to example 2, 230 g of ethyl benzoate and 20 g of diethyl maleate (10 times excess of ethyl benzoate) when initiated and the reaction of 2 g of treg-butyl peroxide (10 mol%) at a temperature of 5 145 s gives 23.5 g (80.5%) of tetraethyl ether 2- (benzoyloxyethyl) -butane-1, 2,3,4-tetracarboxylic acid.

new way opens up the possibility

0 synthesis of previously unavailable tetraalkyl esters of substituted butane-1,2,3, 4-tetracarboxylic acids. A significant advantage of the proposed method is its single-stage,

with the use of readily available substances as starting compounds, the simplicity of experimentally performing the reaction and the distribution of the target product, a. also a high yield of the latter (more than 75%).

0

invention formula

Claims (3)

1. Method of preparing tetraalkyl ethers of substituted butane-1,2, 3, 4-g - tetracarboxylic acids of general formula RQpCCHjCH (COOR) CH (COOR) CH (n) COOR, where R is methyl or ethyl; R-acetoxyhexyl, benzoyloxyethyl and ethyloxaloxysyl, o t l and -. h and y n. and the corresponding carboxylic alkyl ester, taken in 5-io-fold excess, is reacted with dimethyl or diethyl male T in the presence of an organic peroxide initiator in an amount of 10-20 mol%. from maleic acid ester at a temperature of 145- . 2. A method according to claim 1, characterized in that peroxide is used as the initiator of the reaction. t / e-butyl or tert-butyl peroxide.  .-.- : Sources of information taken into account in the examination 1. Japan Patent No. 7372296, cl. 25 (5) D 14, publ. 1971. 2. Modavsky B.D., Babel V.G. Obtaining tetracarboxylic acids by oxidation of unsaturated alicyclic acids. Zh. Prikl.khim. , 1963, 36, 1614. 3. US Patent No. 3218353,. | SL. 260-514, publ. 1965 (prototype)