(1R,4aR,7S,8aS,10aS)-1,4a,7-Trimethyl-7-(2-oxo-ethyl)-1,2,3,4,4a,6,7,8,8a,9,10,10a-dodecahydro-phenanthrene-1-carboxylic acid 2-trimethylsilanyl-ethyl ester 在
4,4'-二氨基二苯乙烯-2,2'-二磺酸 作用下,
以
二氯甲烷 为溶剂,
生成 (1R,4aR,7S,8aS,10aS)-7-(2,2-Difluoro-ethyl)-1,4a,7-trimethyl-1,2,3,4,4a,6,7,8,8a,9,10,10a-dodecahydro-phenanthrene-1-carboxylic acid 2-trimethylsilanyl-ethyl ester