Acylation of 6,7,8,9-tetrahydro-5H-[1,2,4]triazolo-[4,3-a]azepin-3-ylacetonitrile

6,7,8,9-Tetrahydro-5H-[1,2,4]triazolo[4,3-a]azepin-3-ylacetonitrile reacts with carboxylic acid anhydrides and chlorides to afford acylation products at the nitrogen atom in the heteroring or methylene carbon atom, depending on the conditions and nature of the acylating agent. Heating of the N-acyl derivatives leads to migration of the acyl group with formation of C-acyl derivatives.