Process for preparation of (-)3(S)-methylbenzoxazine derivative

摘要

A process for preparing (-)3(S)-methylbenzoxazine derivative of formula (I) comprising the steps of reacting the compound of formula (II) with benzoic acid, triphenylphosphine and diethyl azodicarboxylate in an organic solvent to obtain the compound of formula (III); hydrogenating the compound of formula (III) in the presence of a metallic catalyst to provide the compound of formula (IV); hydrolyzing the compound of formula (IV) to give the compound of formula (V); and reacting the compound of formula (V) with diethyl azodicarboxylate, triphenylphosphine, and zinc chloride in an organic solvent. The obtained (-)3(S)-methylbenzoxazine derivative is a useful intermediate for preparing an antibacterial agent which has a potent bacteriocidal effect. <IMAGE> (I) <IMAGE> (II) <IMAGE> (III) <IMAGE> (IV) <IMAGE> (V)/!