(3R,4S,5S)-4-(tert-Butyl-dimethyl-silanyloxy)-5-{(1R,2S)-1-(tert-butyl-dimethyl-silanyloxy)-2-[(4S,5S)-2-(4-methoxy-phenyl)-5-methyl-[1,3]dioxolan-4-yl]-propyl}-3,5-dimethyl-dihydro-furan-2-one 、
2,2-二甲氧基丙烷 在
四丁基氟化铵 、 camphor-10-sulfonic acid 作用下,
以
四氢呋喃 、
二氯甲烷 为溶剂,
反应 1.5h,
生成 (4R,4aS,7R,7aS)-4-{(S)-1-[(4S,5S)-2-(4-Methoxy-phenyl)-5-methyl-[1,3]dioxolan-4-yl]-ethyl}-2,2,4a,7-tetramethyl-tetrahydro-furo[3,2-d][1,3]dioxin-6-one