Carboxylic acids having the structural formula R.sup.1 COOH, wherein R.sup.1 is a linear, branched or cyclic chain alkyl radical of from 1 to 6 carbon atoms or a phenyl-C.sub.n H.sub.2n -radical wherein 1.ltoreq.n.ltoreq.6, are prepared by carbonylating an alcohol having the formula R.sup.1 -OH with carbon monoxide in liquid phase, in the presence of a catalytically effective amount of nickel and an alkyl or acyl halide promoter therefor, at a temperature of at least about 120.degree. C. and under a total pressure of less than 200 bars, and said carbonylation being carried out in the presence of at least one vanadium compound in which the vanadium is in an oxidation state of 4 or 5, and in an initial carboxylic acid reaction medium having the formula R.sup.2 -COOH, wherein R.sup.2 is defined as was R.sup.1 above, and further wherein R.sup.1 and R.sup.2 may be the same or different.
具有结构式R.sup.1 COOH的
羧酸,其中R.sup.1是由1至6个碳原子构成的线性、支链或环状链烷基基团,或是苯基-C.sub.n H.sub.2n 基团,其中1≤n≤6,通过在液相中,在温度至少为120°C,总压力小于200巴的条件下,使用催化剂量的
镍和烷基或酰基卤素
促进剂,将具有R.sup.1-OH式的醇与
一氧化碳进行羰基化反应制备而成,并且在含有至少一种
钒化合物的条件下进行羰基化反应,其中
钒的氧化态为4或5,并且在初始
羧酸反应介质中具有R.sup.2-COOH式,其中R.sup.2与上述的R.sup.1定义相同或不同。