3,3-bis(methoxycarbonyl)-6-methoxy-1,2,3,4-tetrahydroxynaphthalene-1-spiro-1'-(3'-hydroxycyclohexa-2',5'-dien-4'-one) 在
triethylamine tris(hydrogen fluoride) 、 ethanaminium,N-(difluoro-λ
4-sulfanylidene)-N-ethyl-,tetrafluoroborate 作用下,
以
氯仿 、
异丙醚 为溶剂,
反应 1.5h,
以54%的产率得到6,6-dimethyl 2-fluoro-5,7-dihydro-3-hydroxy-9-methoxy-6H-dibenzo[a,c]cycloheptene-6,6-dicarboxylate