Thionyl Chloride → 4-Chloropyrido(3,4-d)pyrimidine

Participants

Reaction Steps

A suspension of pyrido[3,4-d]pyrimidin-4-ol (33)(1.47 g, 10 mmol) in thionylchloride (30 ml) and dimethylformamide (50 μl, cat.) was heated to reflx (90° C.) for 1 hour. The mixture was then cooled and concentrated in vacuo and then diluted with CH2Cl2 (50 ml) which caused a suspension to form. The solid was removed by filtration, washed with cold CH2Cl2 (10 ml) to give the title compound (1.65 g, 99.4%) in sufficiently pure form to be used without any further purification. m/z (LC-MS, ESP): 166 [M+H]+, R/T=2.82 mins.

Provenance & Evidence