在
六氟合硅酸 作用下,
以
乙腈 为溶剂,
反应 1.5h,
以94%的产率得到[(1R,3'R,4S,5'S,6R,7S,8S,9R,10R,12S,13S,16S,18S)-10-acetyloxy-7-bromo-3'-[tert-butyl(diphenyl)silyl]oxy-8-hydroxy-5'-(hydroxymethyl)-5',7,9,13-tetramethylspiro[5-oxapentacyclo[10.8.0.02,9.04,8.013,18]icos-2-ene-6,2'-oxolane]-16-yl] acetate