(2R,5R)-2-(tert-butyl)-6-hydroxy-5-methoxycarbonyl-8-oxo-7-phenyl-3-oxa-1-azabicyclo[3.3.0]oct-6-ene 、
乙氧甲酰基亚甲基三苯基膦 以
甲苯 为溶剂,
反应 16.0h,
以41%的产率得到(6bS,9R)-9-tert-Butyl-5-ethoxycarbonylmethyl-10-oxo-10H-8-oxa-9a-aza-pentaleno[2,1-a]naphthalene-6b-carboxylic acid methyl ester