Hydrochloric Acid → HCID 22138578, compound

Participants

Reaction Steps

20.0 g of N-benzyl-7-methoxycarbonyl-4H-benz[1,4]oxazin-3-one are initially charged in 750 ml of MeOH. At room temperature, 35 ml of 2N aqueous sodium hydroxide solution are added dropwise, and the mixture is stirred at 40–55° C. for 30 h. The reaction solution is cooled to room temperature and poured into a mixture of 200 ml of 1N HCl and 1 kg of ice. The crude product is filtered off with suction, washed with water and dried. This gives 18.2 g (yield 95.5% of theory) of N-benzyl-7-hydroxycarbonyl-4H-benz[1,4]oxazin-3-one of melting point 230° C.

Provenance & Evidence