(3a'R,6a'S)-5,5-dimethyl-3',3a',4',6a'-tetrahydro-1'H-spiro[[1,3]-dioxane-2,2'-pentalen]-5'-yloxytriethylsilane 、
碘甲烷 在
甲基锂 作用下,
以
四氢呋喃 、
乙醚 为溶剂,
生成 (3a'R,4'R,6a'R)-4',5,5-trimethyl-tetrahydro-1'H-spiro[[1,3]-dioxane-2,2'-pentalen]-5'(3'H)-one 、
(3a'S,4'R,6a'R)-4',5,5-trimethyl-tetrahydro-1'H-spiro[[1,3]-dioxane-2,2'-pentalen]-5'(3'H)-one 、 (3a'R,4'S,6a'S)-4',5,5-trimethyl-tetrahydro-1'H-spiro[[1,3]-dioxane-2,2'-pentalen]-5'(3'H)-one