Studies on ketene and its derivatives. CXVII. Reaction of dichloroketene with ethyl N-(2-pyridyl)formimidates.

Abstract

The reaction of dichloroketene with ethyl N-(2-pyridyl)formimidates (1) gave ethyl 2, 2-dichloro-3-ethoxy-3-(2-pyridylamino)propionates (3) and 3-chloro-2-ethoxypyrido[1, 2-a]pyrimidin-4(4H)-ones (4), together with 3, 3-dichloro-4-ethoxy-1-(2-pyridyl)-2-azetidinone (2). Compound 3b, on standing at room temperature, was transformed into ethyl 2-ethoxy-8-methylimidazo[1, 2-a]pyridine-3-carboxylate (6).