Process for preparing increased molecular weight carboxylic acids and salts thereof from salts of carboxylic acids

摘要

Carboxylic acids of increased molecular weight and salts thereof are prepared by reacting olefines with alkali metal or alkaline earth metal, including magnesium, salts of carboxylic acids free from olefinic and acetylenic unsaturation, said acids having at least one hydrogen atom on an a -carbon atom, in the presence as catalyst of an alkali metal or a hydride or amide thereof at 50-300 DEG C. and at a pressure sufficient to maintain at least a portion of the reactants in liquid form, e.g. about 25-200 atmospheres, dissolving the reaction product in water and recovering the salt of an organic acid of increased molecular weight and/or the acid itself. Suitable olefines include alkenes, cycloalkenes, alkadienes, cycloalkadienes and polyenes; the starting material salts may be derived from mono- or polybasic aliphatic and araliphatic acids. The alkali metal hydrides include mixed hydrides such as lithium aluminium hydride and sodium boro-hydride. Promoters may be used such as aromatic hydrocarbons, organic halides, or alkali metal alkyls or aryls. Inert organic diluents may be present, including hydrocarbons, tertiary amines and ethers; inert gases may also be present. Examples describe the preparation of 2-ethyl- and 2, 2-diethyl-butyric acids from ethylene and sodium or potassium acetate, 2,2-diethylpropionic acid from ethylene and sodium propionate, hexanoic, 2-butylhexanoic and 2,2-dibutylhexanoic acids from 1-butene and sodium acetate, 2-ethyl- and 2,2-diethylstearic acids from ethylene and sodium stearate, 2,2-diethylauric acid from ethylene and sodium laurate, 2-ethylphenylacetic acid from ethylene and sodium phenylacetate, a hexanoic acid of b.pt. 77-78 DEG C. at 1,4 m.m. from 1, 3-butadiene and potassium acetate, and a -methyl-a -ethyl-succinic acid from ethylene and sodium 2-methylsuccinate; the corresponding alkali metal salts are formed as intermediates in each case.