Solvolyses of Polycyclic Cyclobutyl Toluenesulfonate Derivatives

Abstract

A number of isomeric 3-tosyloxytricylo[4.2.1.02, 5] non-7-enes and their corresponding saturated analogues have been prepared and solvolyzed. The chemical behavior of these ROTs esters is of particular interest because the influence of the remote double bond on the developing cation can be tested. In the case of the inside esters (i.e., inside, endo-and exo-1-OTs), the highly strained 2, 5 bond opens in a disrotatory fashion to generate cyclopropylcarbinyl-type rearrangement products. Consistently, the stereochemistry of the actual cyclopropylcarbinyl products mirrors that of the starting material. In the case of the unsaturated esters inside, endo-and exo-1-OTs, the presence of the remote double bonds results in only an inductive rate retardation relative to the corresponding saturated derivatives. The epimeric outside, endo-and exo-1-OTs and the corresponding saturated derivatives solvolyze very slowly with little evidence of 2, 5-bond opening. The outside, endo-2-OTs is the only case where the remote double bond produces relative rate enhancement. The extensive skeletal reorganization in the solvolysis of the rearranged tosylate 6 again illustrates the importance of orbital alignment in the ground state for participation in the course of a solvolysis reaction. © 1978, American Chemical Society. All rights reserved.