(5R,6S)-6-[(R)-1-(tert-Butyl-dimethyl-silanyloxy)-ethyl]-3-(2-hydroxy-ethanesulfonylmethyl)-7-oxo-4-thia-1-aza-bicyclo[3.2.0]hept-2-ene-2-carboxylic acid allyl ester 在
1-甲基吡咯烷 、
三氟甲磺酸酐 作用下,
以
二氯甲烷 为溶剂,
以30%的产率得到(5R,6S)-6-[(R)-1-(tert-Butyl-dimethyl-silanyloxy)-ethyl]-3-ethenesulfonylmethyl-7-oxo-4-thia-1-aza-bicyclo[3.2.0]hept-2-ene-2-carboxylic acid allyl ester