Lewis acid promoted reaction of pentacyclo[5.4.0.02,6.03,10.05,9]undecane-8,11-dione with ethyl diazoacetate: a synthetic entry into the pentacyclo[6.5.0.04,12.05,10.09,13]tridecane ring system
Lewis acid promoted reaction of pentacyclo[5.4.0.02,6.03,10.05,9]undecane-8,11-dione with ethyl diazoacetate: a synthetic entry into the pentacyclo[6.5.0.04,12.05,10.09,13]tridecane ring system