Phosphorus pentachloride → 6-chloro-11H-benzo[e]pyrido[3,2-b][1,4]diazepine

Participants

Reaction Steps

A solution of 5H-benzo[e]pyrido[3,2-b][1,4]diazepin-6(11H)-one (18 g, 85.3 mmol) and PCl5 (20.5 g) in dichloromethane (650 mL) was stirred at reflux until the starting material was all consumed (use LC/MS to follow the reaction). The reaction mixture was concentrated in vacuo to half volume and the resulting solid was collected by filtration and washed with dichloromethane. The filtrate was further concentrated and a second crop was similarly obtained and combined. The 6-chloro-11H-benzo[e]pyrido[3,2-b][1,4]diazepine was obtained as a yellow solid (total 14 g, 71%). LCMS [M+H]: 230.

Provenance & Evidence