Substrate- and base-dependent reactivities of acylketene toward aryl aldimines derived from 2-amino-4-methylpyridine

Acylketene, generated from 2,2,6-trimethyl-4H-1,3-dioxin-4-one reacts with aryl aldimines derived from 4-methyl-2-aminopyridine to give a variety of products, depending on the substituent on the C-aryl group, base used, and hydrolytic stability of the starting aldimine. Also the presence of the N-(2-pyridyl) group plays an important role in the fate of the reaction course, frequently participating in intramolecular conjugate additions, giving rise to interesting heterocycles. (C) 2015 Elsevier Ltd. All rights reserved.