4-(2,2-dimethylpent-4-en-1-yl)-coumarin 在
((3aS)-3,3-bis(3,5-dimethylphenyl)-1-(2-(trifluoromethyl)phenyl)hexahydro-1H-pyrrolo[1,2-c][1,3,2]oxazaborol-7-ium-7-yl)tribromoaluminate 作用下,
以
二氯甲烷 为溶剂,
反应 4.5h,
生成 (3aS,4aR,10bS)-2.2-dimethyl-3,3a,4,4a-tetrahydro-1H-cyclopenta[2,3]-cyclobuta[1,2-c]chromen-5(2H)-one 、
(3aR,4aS,10bR)-2.2-dimethyl-3,3a,4,4a-tetrahydro-1H-cyclopenta[2,3]-cyclobuta[1,2-c]chromen-5(2H)-one