Novel rearrangement of conformationally restrained [3.3]orthocyclophanes

Abstract

Novel rearrangement of intermediate carbocations generated from rigid, layered [3.3]orthocyclophane-alcohols 4 are presented. The bicyclo[4.4.1]undecane framework of 4 rearranges to either bicyclo[5.4.0]- 5 and/or bicyclo[4.4.0]- 6 or tricyclo[5.4.0.0^2,11]- ring-system 11, depending upon the nature of the aryl substituent on the bridging tertiary carbon atom. X-Ray crystal structure analyses have been performed on the rearrangement products.