dimethyl (E)-2-(4-methoxystyryl)malonate 、
dimethyl 2-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)cyclopropane-1,1-dicarboxylate 在
tin(II) trifluoromethanesulfonate 作用下,
以
硝基甲烷 为溶剂,
反应 0.5h,
以77%的产率得到dimethyl ({(6RS,7SR,8SR)-7-[2-methoxy-1-(methoxycarbonyl)-2-oxoethyl]-8-(4-methoxyphenyl)-2,3,7,8-tetrahydro-6H-indeno[5,6-b][1,4]dioxin-6-yl}methyl)malonate