6-(4-methoxybenzylidene)-3,4-methylenedioxycyclohexa-2,4-dienone 、
methyl phenyl ketene 在
甲醇 、
(S)-5-((tert-butyldimethylsilyloxy)diphenylmethyl)-2-phenyl-6,7-dihydro-5H-pyrrolo[2,1-c][1,2,4]triazol-2-ium tetrafluoroborate 、
caesium carbonate 作用下,
以
乙二醇二甲醚 为溶剂,
反应 0.08h,
生成
(7R,8S)-8-(4-methoxyphenyl)-7-methyl-7-phenyl-7,8-dihydro-[1,3]dioxolo[4,5-g]coumarin 、 (7S,8R)-8-(4-methoxyphenyl)-7-methyl-7-phenyl-7,8-dihydro-[1,3]dioxolo[4,5-g]coumarin 、 8-(4-methoxyphenyl)-7-methyl-7-phenyl-7,8-dihydro-[1,3]dioxolo[4,5-g]coumarin