2-Aminopyridine → 2-(chloromethyl)-4H-pyrido[1,2-a]pyrimidin-4-one

Participants

Reaction Steps

37.7 g 2-pyridinamine was dissolved in about 250 g polyphosphoric acid, at 40°-50°, using a mechanically driven stirrer. To this mixture was added, dropwise, 54 ml ethyl 4-chloroacetoacetate. After the addition, the mixture was heated to about 125° for 1/2 hour. After cooling to about 50°, the mixture was poured into 1500 ml of ice water, and the mixture was extracted with an equal volume of chloroform. After drying and evaporation of chloroform, about 45 g 2-(chloromethyl)-4H-pyrido[1,2-a]pyrimidin-4-one (m.p. 171°-174°) was obtained.

Provenance & Evidence