Method for production of trans-alkyl-substituted cyclohexanecarboxylic acids

FIELD: organic chemistry.

SUBSTANCE: invention relates to improve method for production of trans-alkyl-substituted cyclohexanecarboxylic acids of general formula 1 , wherein R is C1-C10-alkyl and trans-4-(C1-C10-alkyl)cyclohexyl radical, by hydration of respective 4-alkyl-substituted benzoic acids. In aqueous-alkali solution at elevated temperature and elevated hydrogen pressure of 0.5-15 MPa in presence of catalyst followed by isomerization at 200-400°C and isolation of reaction products by mixture acidifying. As catalyst ruthenium-nickel catalyst on carbon carrier is used, wherein catalyst contains 5 mass % of metal calculated as total catalyst mass and Ni/Ru mass ratio is (0.01-1.5):(8.5-9.99). Process is carried out at 20-150°C for 0.25-1 h, and isomerization is carried out in inert gas atmosphere in several steps after mixture filtration to separate catalyst. Compounds of present invention represent value products in production of liquid crystal materials and biologically active materials.

EFFECT: accelerated process with reduced cost and increased effectiveness.

1 tbl, 9 ex

 

The invention relates to the field of industrial organic synthesis, namely the improvement of the method of producing TRANS-4-substituted cyclohexanecarboxylic acids of the General formula:

(where R is alkyl and TRANS-4-alkylcyclohexane radical with the number of carbon atoms from one to ten in the alkyl group), by hydrogenation of the corresponding 4-alkyl substituted benzoic acids in the presence of ruthenium-Nickel catalyst on a carrier with a metal content of 5 wt.% in the calculation of the entire catalyst, which are valuable intermediates for obtaining as liquid crystal materials, and biologically active compounds.

A method of obtaining substituted cyclohexanecarboxylic acids of General formulawhere R - NH2CH2(aminomethyl) by hydrogenation of the corresponding substituted benzoic acid in aqueous-alkaline solution under a pressure of 5-20 MPa when heated to 90-200°in the presence of ruthenium catalyst [U.S. Patent No. 3932497, CL 562/507, 562/442, C 07 C 51/36, publ. 1976]. The output of the TRANS-isomer of 30-40%. The main disadvantages of this method are: low yield of the TRANS isomer, relatively stringent process conditions, namely high pressure of 5-20 MPa, high temperature reaction 90-200°With, fast trawl is the catalyst.

The closest in technical essence and the achieved results is the way to obtain TRANS-4-substituted cyclohexanecarboxylic acids of General formula

(where R is alkyl or CNS group with the number of carbon atoms of from one to eighteen) by catalytic hydrogenation of the corresponding 4-alkyl substituted benzoic acids in aqueous-alkaline solution under pressure, when heated, in the presence of a ruthenium catalyst, followed by isomerization in the presence of hydrogen without separation of the reaction mixture from the ruthenium catalyst, and separating the product by acidification of the mixture [Japan Patent No. 9040606, class C 07 C 61/08, B 01 J 23/46, C 07 C 51/36, C 07 C 62/10, publ. 1997]. The process is performed for 0.5 to 8 hours (preferably 0.5 to 2 hours) at a pressure of 0.5 to 15 MPa, a temperature of 50-150°C, the temperature of the isomerization 200-400°and as ruthenium catalyst used catalyst with a metal content of 5%, the output alkylcyclohexanes acid 90% when the output of the TRANS-isomer of 60-70%. The main disadvantages of this method are the relatively low yield of the TRANS isomer, the possibility of occurrence of adverse reactions during high-temperature isomerization in the presence of a ruthenium catalyst.

The problem solved by the present invention is to increase the efficiency of the process is Holocene TRANS-4-alkylcyclohexane acids by increasing the yield of the target product and the cost of the catalyst.

The proposed method of producing TRANS-4-alkyl substituted cyclohexanecarboxylic acids is the hydrogenation of the corresponding alkylbenzoic acids with hydrogen in an aqueous-alkaline medium at a temperature of 20-150°and davlenie 0.5 to 15 MPa in the presence of ruthenium-Nickel catalyst supported on carbon, with a metal content of 5 wt.% in the calculation on the entire catalyst at a mass ratio of Ni:Ru(0,01-1,5):(8,5-9,99) with the subsequent isomerization of the product in an atmosphere of inert gas at a temperature of 200-400°C. the isomerization Process is carried out in several stages after filtering the mixture to separate the catalyst and the allocation of TRANS-isomer at each stage.

The first distinguishing feature of the present invention should be considered as the use of ruthenium-Nickel catalyst supported on carbon, with a metal content of 5 wt.% in the calculation on the entire catalyst at a mass ratio of Ni:Ru(0,01-1,5):(8,5-9,99). A method of obtaining substituted cyclohexanecarboxylic acids by hydrogenation of the corresponding aromatic carboxylic acids to the catalyst containing ruthenium and Nickel coal with a content of 0.01 to 30 wt.% metal based on the whole catalyst with different ratios of Ru and Ni [US 5936126, publ. 10.08.1999]. In this way the ratio of ruthenium and Nickel, however, when the Nickel content of catalizzatore more than 20% based on the weight of the entire metal observed a significant reduction in the reaction rate and incomplete conversion of the original aromatic acids, that reduces the yield of the target product and makes it difficult for its selection.

The second hallmark is conducting isomerization process in several stages. After the first stage of isomerization of the content of the TRANS-isomer is approximately 80%, and the CIS isomer is 20%, which corresponds to an equilibrium state, so the output after this stage cannot preisach 80%. The several stages of isomerization with the separation of the target product at each stage allows to increase the output of the TRANS-isomer to 95-98% and make the process without waste.

The hydrogenation is carried out in an autoclave with intensive stirring, in the lower part of which provides the conclusion of the reaction mass. In the autoclave load water-alkaline solution of 4-substituted benzoic acid and ruthenium-Nickel catalyst. The autoclave is rinsed with nitrogen, create the desired hydrogen pressure and heated with stirring until the absorption of hydrogen (0.25 to 1 h). After dropping the pressure of the reaction mass through the lower output of the autoclave is separated from the ruthenium-Nickel catalyst by filtration and vyderjivaut for 0.5-1 h at 200-400°C in an atmosphere of inert gas. By acidification of an aqueous-alkaline solution of hydrochloric acid to produce a mixture of CIS - and TRANS-4-alkyl substituted cyclohexanecarboxylic acid (the content of the TRANS-isomer 7-85%) and freezing of hexane get pure TRANS-isomer. The mother solution after Stripping hexane is again dissolved in aqueous alkali and subjected to repeated thermal isomerization in the described manner. After 4-fold repetition of the isomerization process output TRANS-alkylcyclohexanes acid reaches 95-98%. The same ruthenium-Nickel catalyst can be used without significant loss of activity during 15 cycles of hydrogenation.

The invention is illustrated by the following examples.

Example 1

In the autoclave with a capacity of 2 l, equipped with a high-speed stirrer, load 350 g (1.97 mol) of n-butylbenzoic acid and 18.5 g of ruthenium-Nickel catalyst (ratio of Ni:Ru=1:9), 1 liter of distilled water, or 110.3 g of KOH (1,97 mol). The reaction is carried out at 100°and a hydrogen pressure of 4 MPa. The absorption of hydrogen ends after 0.5 h after start of the reaction. After dropping the pressure of the reaction mass is separated from the ruthenium-Nickel catalyst by filtration and subjected to thermal isomerization by keeping within 1,0 h at 200-300°C in an atmosphere of inert gas to the content of the TRANS-isomer 75%. The pure TRANS-isomer is isolated by acidification of the reaction mixture with HCl to pH=2 and recrystallization from hexane. The mother liquor after removal of the hexane and dissolution of the residue in aqueous alkali is subjected to re-isomerization. The output of transisomer 4-n-ethylcyclohexylamine acid after 4 recyclo is 343 g (95%), TPL 41°C.

The table below shows examples 1-10 hydrogenation alkylbenzoic acids in the presence of ruthenium-Nickel catalyst. Processing of the reaction mixture, thermal isomerization and separation of the TRANS-isomer in all experiments similar.

Thus, the proposed method of producing TRANS-4-zemedeneh cyclohexanecarbonyl acids using ruthenium-Nickel catalyst, means:

1) to increase the yield of the target product through several stages of thermal isomerization after filtering the mixture to separate the catalyst;

2) to avoid the occurrence of adverse reactions, as well as additional mechanical wear of the catalyst and to increase the service life of the catalyst due to the promotion Nickel, which leads to a decrease in the rate of poisoning due to the greater stability of the system to catalytic poisons.

The developed method can be used for industrial production of ruthenium-Nickel catalyst and TRANS-4-substituted cyclohexanecarboxylic acids.

Table

Hydrogenation alkylbenzoic acids in the presence of ruthenium-Nickel catalyst
No. sampleThe radical RThe mass of the acid, g The ratio of Ni:ENThe mass of catalyst, gP, MPaT °Reaction time, hThe output of the TRANS-isomer, %The number recyclo
1n-C4H9-3501:918,541000,5954
2n-C4H9-3500,01:9,9918,541000,8905
3n-C4H9-3502,0:8,018,5410055.0 when the degree of conversion 20%1
4CH3-1361:96,841000,4964
5CH3-1361:96,841000,4985
6n-C3H7-1641:98,241000,65944
7 n-C3H7-(prototype)123,15% EN6,251301,560,41
8n-C10H21-1311:96,541000,75965
91261:96,341000,8945
101401:97,041000,8925

The way to obtain TRANS-4-alkyl substituted cyclohexanecarboxylic acids of the General formula:

where R is alkyl and TRANS-4-alkylcyclohexane radical with the number of carbon atoms from one to ten in the alkyl group, by hydrogenation of the corresponding 4-alkyl substituted benzoic acids in aqueous-alkaline solution at elevated temperature and elevated hydrogen pressure of 0.5 to 15 MPa in the presence of a catalyst followed by isomerization at a temperature of 200-400°and the release of the reaction products of isomerization of acidification sm is si, characterized in that a catalyst is used ruthenium-Nickel catalyst supported on carbon, with a metal content of 5 wt.% in the calculation on the entire catalyst at a mass ratio of Ni:Ru(0,01-1,5):(8,5-9,99), the process of hydrogenation is carried out at a temperature of 20-150°C for 0.25 to 1 h, and the isomerization process is carried out in an atmosphere of inert gas in several stages after filtering the mixture to separate the catalyst.



 

Same patents:

The invention relates to an improved method for producing a synthetic succinic acid, similar in biological activity of succinic acid obtained by the pyrolysis of amber, used as a drug or biologically active food supplements

The invention relates to an improved method for producing a p-hydroxymandelic compounds by condensation in the water, in the presence of an alkaline agent, an aromatic compound containing at least one hydroxyl group and having a free parapolitica, with Glyoxylic acid

The invention relates to the industrial production monochloracetic acid
The invention relates to a method for oleic acid, whereby carry out the hydrogenation of fatty acids of tall oil on the catalyst Ni/kieselguhr at a temperature of 140-160oC and a pressure of 0.5-1.0 MPa for 0.5-1.0 hours

The invention relates to a method for producing 4-chlorophenoxyacetic or 2,4-dichlorophenoxyacetic acid (2,4-D)

The invention relates to the production of acetic acid and/or methyl acetate

The invention relates to an improved method for the removal of formaldehyde or its adducts of organic liquid mixtures obtained in the production of methyl methacrylate containing at least a carboxylic acid or an ester of carboxylic acid and formaldehyde or its adducts, which forms a two-phase mixture of water, comprising at least one extraction liquid organic mixture in the system liquid-liquid using water as the extractant with getting the flow of the organic phase and flow of the aqueous phase, and the flow of the organic phase contains significantly reduced the concentration of formaldehyde or its adducts compared with the liquid organic mixture

The invention relates to an improved process for the preparation of methyl methacrylate, comprising the stages of (i) interaction propionic acid or its ester with formaldehyde or its predecessor in the condensation reaction with the formation of the stream of gaseous products containing methyl methacrylate, residual reactants, methanol and by-products, (ii) processing at least one portion of the stream of gaseous products with the formation of a stream of liquid products containing almost all of the methyl methacrylate and at least one impurity, which melts at a temperature above the melting temperature of pure methyl methacrylate, run over the flow of the liquid product at least one operation fractional crystallization, which contains the stage (iii) cooling the specified flow of liquid product to a temperature between about -45oAnd about -95oSo that the flow of liquid product forms solid crystals of methyl methacrylate and uterine fluid, and these crystals have a higher content of methyl methacrylate than the specified stream of liquid products or uterine fluid, (iv) the separation of these crystals of solid methyl methacrylate from the specified match Azania impurity in a lower concentration, than the specified stream of liquid products
The invention relates to a technology for production of acetic acid and its derivatives by isomerization of methylformate in the presence of water, aliphatic carboxylic acid WITH1-C10as solvent and catalyst system
The invention relates to a process for producing products of natural resins and can be used in chemical, petrochemical and other industries that manufacture and use of surface-active substances, in particular in the production of synthetic rubber

FIELD: organic chemistry.

SUBSTANCE: invention relates to improve method for production of trans-alkyl-substituted cyclohexanecarboxylic acids of general formula 1 , wherein R is C1-C10-alkyl and trans-4-(C1-C10-alkyl)cyclohexyl radical, by hydration of respective 4-alkyl-substituted benzoic acids. In aqueous-alkali solution at elevated temperature and elevated hydrogen pressure of 0.5-15 MPa in presence of catalyst followed by isomerization at 200-400°C and isolation of reaction products by mixture acidifying. As catalyst ruthenium-nickel catalyst on carbon carrier is used, wherein catalyst contains 5 mass % of metal calculated as total catalyst mass and Ni/Ru mass ratio is (0.01-1.5):(8.5-9.99). Process is carried out at 20-150°C for 0.25-1 h, and isomerization is carried out in inert gas atmosphere in several steps after mixture filtration to separate catalyst. Compounds of present invention represent value products in production of liquid crystal materials and biologically active materials.

EFFECT: accelerated process with reduced cost and increased effectiveness.

1 tbl, 9 ex

FIELD: chemistry.

SUBSTANCE: invention relates to improved method of salicylates of alkaline earth metals for application as detergents for lubricating materials. Method of obtaining alkylated salicytates of alkaline earth metals includes following stages: A) alkylating salicylic acid with linear α-olefin, containing, at last, 14 carbon atoms, in presence of water-free methane sulfonic acid with formation of oil-soluble alkylated salicylic acid; B) neutralisation of oil-soluble alkylated salicylic acid; C) excessive alkalisation of oil-soluble alkylated salicylic acid by carboxylating lime by means of CO2 in presence of oxygen-containing organic solvent and surface-active substance; D) filtration of stage (C) product; and E) removal of solvent by distillation. Alternatively, alkylsalicylic acid can be subjected to interaction with preliminary processed with alkali highly-alkaline sulfonate of earth alkaline metal, for instance, with calcium sulfonate, in order to obtain salicylate salts of earth alkaline metals with different per cent content of dispersed salts of alkaline earth metals carbonates. In claimed method it is not necessary to filter end product which is preferable doe industry.

EFFECT: obtaining salicylates of alkaline earth metals for application as detergents for lubricating materials.

8 cl, 4 ex

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing α-hydroxycarboxylic acids, particularly a novel method of producing 2-hydroxy-carboxyalkyladamantanes of general formula where R=H, CH3, which can be used as intermediate products in synthesis of adamantyl-containing amino acids and heterocyclic compounds. The method includes reacting adamantanone-2 with dilithium salts of acetic or propionic acid, obtained in situ by reacting lithium acetate or propionate with lithium hexamethyldisilylamide, obtained beforehand from hexamethyldisilazane and phenyllithium, in the medium of dry tetrahydrofuran at 20-45°C and molar ratio hexamethyldisilazane: lithium acetate or propionate: adamantanone-2 of 1.3-1.4:1.8-2.1:1.

EFFECT: wider range of compounds of the disclosed structural formula and obtaining products with high output and high degree of purity.

2 ex

FIELD: chemistry.

SUBSTANCE: invention relates to a method of obtaining highly fluorinated carboxylic acids and their salts, as well as substances-precursors, which includes an impact on a highly fluorinated olefin, which has the general formula (I): Rf-(O)n-(CF2)m-CF=CF2 of a formic acid derivative in accordance with the general formula (II): HCOR in the presence of a radical initiator to form a substance-precursor of carboxylic acid in the form of O-ethers, S-ethers or an amide adduct of the general formula (III): Rf-(O)n-(CF2)m-CFH-CF2-COO and, optionally, in case of an acid obtaining, hydrolysis of an adduct of formula (III) to form carboxylic acid or its salts with the general formula (IV): Rf-(O)n-(CF2)m-CFH-CF2-COO-M+, where in formulas (II) and (III) R represents a residue O-M+, S-M+, OR' or SR' or NR'R", where R' and R" are independent on each other linear or branched or cyclic aliphatic residues, which contain at least one carbon atom and which do not have an alpha-H-atom, where the alpha-H-atom represents a hydrogen atom, bond with a carbon atom, bound with O, S or N in groups OR', SR' or NR'R", and where in formulas (I), (III), (IV) Rf represents H, either a perfluorinated or fluorinated linear or branched alkyl residue which can contain one or several catenary oxygen atoms, and n constitutes 1 or 0, m represents a number from 0 to 6, and M+ represents a cation.

EFFECT: method makes it possible to obtain target compounds with the high output.

8 cl, 7 ex

Up!