(3-allyloxycarbonyl-2-oxo-propylidene)triphenylphosphorane 、 2-[2-((R)-2,2-Dimethyl-[1,3]dioxolan-4-yl)-2-oxo-ethylidene]-malonic acid dimethyl ester 在
仲丁基锂 作用下,
以
四氢呋喃 为溶剂,
生成 2-[(1S,5R)-5-Allyloxycarbonyl-2-((R)-2,2-dimethyl-[1,3]dioxolan-4-yl)-4-oxo-cyclopent-2-enyl]-malonic acid dimethyl ester 、
2-[(1R,5S)-5-Allyloxycarbonyl-2-((S)-2,2-dimethyl-[1,3]dioxolan-4-yl)-4-oxo-cyclopent-2-enyl]-malonic acid dimethyl ester