N,N-二甲基乙酰胺 、
(2R)-2-[(1R,5S)-3-phenyl-7-oxo-4-oxa-2,6-diazabicyclo[3.2.0]hept-2-en-6-yl]-3-iodomethyl-3-butenoic acid diphenylmethyl ester 在
silver tetrafluoroborate 作用下,
以82%的产率得到(R)-3-Acetoxymethyl-2-((1R,5S)-7-oxo-3-phenyl-4-oxa-2,6-diaza-bicyclo[3.2.0]hept-2-en-6-yl)-but-3-enoic acid benzhydryl ester