JPS6125421B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a catalyst for the esterification reaction between an organic carboxylic acid and a vicinal epoxide, which consists of a combination of an organic amine compound and a chromium compound. The invention also relates to a process for the production of beta-hydroxy esters, which consists in reacting an organic carboxylic acid with a vicinal epoxide at a temperature of 60 to 130° C., characterized in that a catalytic amount of the abovementioned catalyst is used. . The chromium compounds include chromium halides, chromium acetylacetonate, chromium oxide or mixtures thereof. A synergistic catalytic effect means a catalytic effect that is greater than the theoretical sum of the catalytic effects of the amino and chromium catalysts used separately. The catalyst composition of the present invention has an unexpected positive effect on reaction rate and product yield. Preferred organic amine compounds are compounds containing a tertiary nitrogen atom, such as trialkylamines, trialkanolamines, dialkylarylamines, diarylalkylamines, triarylamines, trialkylamines, trialkelylamines. , dialkylaralkylamines, dialkylalkarylamines, dialkylcycloalkylamines, pyridine, etc.
or a 6-membered heterocyclic aromatic, and 1 in the ring
is a 6-membered heterocycloaliphatic containing nitrogen atoms, and the compound may contain a secondary nitrogen atom or an oxygen or sulfur atom within the ring, such as N-substituted piperidine and piperazine and aminophenol. . Compounds containing primary and/or secondary amino groups are suitable, however, such amino compounds first react with an epoxide reactant to form a tertiary alkanolamine, and then the tertiary alkanol The amine acts catalytically like other tertiary amines. However, there are no particular advantages to using primary or secondary amines. Suitable compounds containing quaternary ammonium nitrogen are generally tetraalkylammonium halides, including amino-containing ion exchange resins. Examples of suitable amine compounds are butylamine, ethylenediamine, diethylenetriamine,
Dipropyleneamine, trimethylamine, triethylamine, tributylamine, trioctylamine, triethanolamine, tributanolamine, N/N-dipropylphenylamine, diphenylpropylamine, triphenylamine, triphenethylamine, tritolylamine, N・N
-dimethylphenethylamine, N/N-diethylbenzylamine, N-methyl-N-hexylphenethylamine, N/N-dibutyltolylamine,
N・N-diethylcyclohexylamine, piperidine, N-ethylpiperidine, N-phenylpiperidine, piperazine, N・N'-diethylpiperazine, N-phelpiperazine, N-methylmorpholine, N-butylpyrrolidine, pyridine, tetramethyl Ammonium chloride, tetraethylammonium bromide, ammonium chloride and tris(dimethylaminomethyl)phenol. Suitable chromium compounds are the known classes of chromium salts and organometallic complexes that are known to dissolve in acid or epoxy reactants and to catalyze esterification reactions. Preferred compounds are chromium halides, chromium acetylacetonate and chromium oxide. Generally hexahydrate CrCl ₃ .
Chromium chloride, available as 6H ₂ O, is also preferred. The catalyst system as defined above is a combination of an amine catalyst and a chromium catalyst. Examples of such combinations are triethylamine and chromium chloride, N.N-
Chromium complexes of diethylcyclohexylamine and chromium bromide, triethylamine and pyridine (py), such as Cr(py) ₃ Cl ₃ and Cr(py) ₂ (H ₂ C)
Contains Cl ₃ , and tris(dimethylaminomethyl)phenol and chromium chloride. The preferred ratio of amine to chromium catalyst to provide a synergistic effect is a molar ratio of amino nitrogen to chromium ion of 1:10 to 10:1; Even within the range, it is extremely microscopic. The catalyst is based on the weight of the acid from 0.0005 to
Present in the esterification reaction in an amount of 0.05% by weight. Preferably, it is present in an amount of 0.001 to 0.01% by weight. The amine and chromium catalyst can be incorporated into the reaction mixture in any order, such as (a) such compounds are first mixed with each other and then added to the acid or epoxy reactant or mixture thereof; (b) The chromium compound is first dissolved in the acid reactant and the amine is added either separately or in combination with the epoxide. Methods in which the chromium compound is first dissolved in the acid are generally preferred. This is because it ensures a more homogeneous mixture of catalyst and reactants. The amine and chromium catalysts as well as the carboxylic acids and vicinal copoxides in the esterification reaction are generally known. For example, typical acid reactants include alkane mono- or dicarboxylic acids, aromatic mono- or dicarboxylic acids, and those acids substituted with hydroxy or halogens, such as acetic acid, propionic acid,
Cabroic acid, stearic acid, acrylic acid, methylacrylic acid, malonic acid, adipic acid, maleic acid, benzoic acid, phenylacetic acid, naphthenic acid, toluic acid, terephthalic acid, α-bromoglutanic acid,
Includes salicylic acid, p-chlorobenzoic acid, m-methoxybenzoic acid and beta-hydroxybenzoic acid. Suitable epoxide reactants generally include alkylene epoxides having 2 to 4 carbon atoms, namely ethylene oxide, propylene oxide and butylene oxide, and epihalohydrins such as epichlorohydrin, mono- and di- and polyglycidyl ethers and styrene oxide. Also includes. Example 1 21.6 g (0.3 mol) of glacial acrylic acid in a reaction bottle,
0.1108 g (0.4 mmol) of CrCl ₃ .6H ₂ O, 26.4 g (0.6 mmol) of ethylene oxide and 0.084 g (0.8 mmol) of triethylamine were charged. that bottle
Placed in an 80°C water bath and stirred for 30 minutes. The bottle was removed from the bath and opened. Excess ethylene oxide was removed under reduced pressure.
The product was weighed and titrated for unreacted acid. The product weighed 35.3 g and contained 8.3% by weight unreacted acid. Example 2 The compound CrCl _{3.6H 2} O was converted into Cr(py) ₂ (H ₂ O)
Example 1 except that the substitution was made with 0.1681 g (0.5 mol) of Cl ₃
The procedure was repeated. After removing excess ethylene oxide from the product, the product weighed 38.1 g and contained 0.57 weight of residual acid. Example 3 8.3 g (0.05 mol) of terephthalic acid in the reaction bottle,
Dioxane 20g, acetylacetone chromium Cr
(C ₅ H ₇ O ₂ ) ₃ 0.17 g (0.5 mmol), and pyridine
0.32 g (4 mmol) was added. Then 4.4 g (0.1 mole) of ethylene oxide was added, the bottle was capped and placed in a rotary steam autoclave where it was heated to 100° C. for 30 minutes. The pin was then removed from the autoclave, cooled, opened and the bath agent and unreacted ethylene oxide removed under reduced pressure. The reaction product was weighed and a portion thereof was titrated to determine the amount of acid remaining. The reaction product was found to contain 33.8% by weight of residual acids such as terephthalic acid. Example 4 The procedure of Example 3 was repeated using 0.05 g (0.5 mmol) of chromium oxide CrO ₃ in place of the chromium acetylacetonate. The reaction product was found to contain 53.4% by weight of residual acids such as terephthalic acid. Examples 5, 6 and Comparative Runs A and B 21.6 g of glacial acrylic acid in each of 5 reaction bottles
(0.3 mol) and propylene oxide 34.8 g (0.6
mol) was added. Into each bottle were then added chromium acetonate, Cr(C ₅ H ₇ O ₂ ) ₃ or Cr(AA) ₃ and triethylamine, TEA having a molecular weight of 349.32 in the amounts shown in Table 1. The bottle was capped and placed in a rotary steam autoclave where it was heated to 100°C for 1 hour. Then, the bottle was removed from the autoclave, cooled, opened, and evaporated to a constant weight of 150 mm.
It was removed at a pressure of 50°C. The remaining product was weighed and 1 g of it was titrated with 0.1N NaOH to pH 7 to determine the residual acid in the reaction product.

TABLE These examples show that chromium acetylacetone, Cr(AA ) shows the synergistic effect of the combination of ₃ and triethylamine.

Claims (1)

[Scope of Claims] 1. A catalyst for an esterification reaction between an organic carboxylic acid and a vicinal epoxide, comprising a combination of an organic amine compound and a chromium compound consisting of a chromium halide, chromium acetylacetone, chromium oxide, or a mixture thereof. 2. The catalyst according to claim 1, wherein the chromium compound is chromium chloride. 3 Organic carboxylic acid and vicinal epoxide are mixed at a temperature of 60°C to 130°C using a catalyst consisting of a combination of an organic amine compound and a chromium compound consisting of chromium halide, chromium acetylacetone, chromium oxide, or a mixture thereof. A method of producing beta hydroxy esters comprising reacting.