Abstract: Process for the preparation of 2-acetylcarboxylic esters by reacting an acetoacetic ester having 1 to 6 C atoms in the alkyl moiety with an aliphatic aldehyde having 1 to 12 C atoms at 0 to 40.degree. C. in the presence of a condensation catalyst, subsequently removing the water of reaction formed and unreacted starting materials and then hydrogenating the material at 20-160.degree. C., the temperature in the first hydrogenation phase being between 20 and 90.degree. C. and the temperature in the second phase being increased to 50 to 160.degree. C., depending on the starting temperature.

Abstract: Process for the preparation of carboxylic acid succinimidyl esters by reaction of N-hydroxysuccinimide with a carboxylic acid and a halophosphoric acid ester of the formula ##STR1## in which R.sub.1 and R.sub.2 are identical or different and are a C.sub.2 - to C.sub.6 -alkyl radical or a phenyl radical, or R.sub.1 and R.sub.2 together form a C.sub.6 -aryl radical, in the presence of a base in a diluent at a temperature of 0.degree. C. up to 100.degree. C. and isolation of the corresponding carboxylic acid succinimidyl ester.

Abstract: A process for the preparation of carboxylic acid succinimidyl esters by reaction of N-hydroxysuccinimide with a carboxylic acid and a halophosphoric acid ester of the formula ##STR1## is desired, in which R.sub.1 and R.sub.2 are identical or different and are a C.sub.2 - to C.sub.6 -alkyl radical or a phenyl radical, or R.sub.1 and R.sub.2 The process is carried out in the presence of a base in a diluent at a temperature of 0.degree. C. up to 100.degree. C. with isolation of the corresponding carboxylic acid succinimidyl ester.