环戊二烯 、
methyl <5R-(5α,6α)>-5,6,7,8-tetrahydro-7-methylidene-8-oxo-5-(3,4,5-trimethoxyphenyl)naphtho<2,3-d><1,3>dioxole-6-carboxylate 以
乙醚 为溶剂,
反应 15.0h,
以10%的产率得到methyl (6S,7R,8R,1'R,4'R)-5,6,7,8-tetrahydro-5-oxo-8-(3,4,5-trimethoxyphenyl)naphtho<2,3-d><1,3>dioxole-6-exo-spiro-5'-(bicyclo<2.2.1>hept-2-ene)-7-carboxylate