N-vinylamides and a process for preparing them

摘要

N-Vinylamides of the formula wherein X represents a carbonyl or sulphonyl group and R and R1 each represent an aliphatic, cycloaliphatic, araliphatic or aromatic radical or, if X represents the carbonyl group, may be linked to form a heterocyclic ring containing the nitrogen atom, are prepared by reacting acetylene with an amide of the formula R-X-NH-R1 in the liquid phase, in the presence of a basic catalyst, at a pressure not exceeding 2.5 atmospheres (gauge) and at a temperature between 90 DEG and 300 DEG C., the N-vinylamide being removed from the reaction core as it is formed. The invention also comprises the compounds N-vinyl-N-ethyl-propionamide, N - vinyl - N - methyl - isobutyramide and N-vinyl-N-isopropyl-acetamide. The reaction may be conducted in the presence of a basic catalyst, many being specified. An especially suitable catalyst is an alkali metal compound of the amide starting material, which compound is preferably prepared in situ by dissolving the appropriate alkali metal or a compound thereof in the amide to be vinylated.