A study of cations generated from 1-Methyl- and 7, 7-Dimethyl-2-phenyIbicyclo[2, 2, l]heptan-2-oIs

Abstract

Attempts to generate the l-methyl-2-phenylbicyclo[2, 2, l]hept-2-yl cation (6) by reaction of 1-methyl-exo-2-phenylbicyclo[2, 2, l]heptan-endo-2-ol (5) with HSO3F in SO2C1F were not successful, due to spontaneous rearrangement to endo-6-methyl-2-phenylbicyclo[2, 2, l]hept-2-yl cation (7). This cation (7) itself rearranges at higher temperatures to exo-6-methyl-2-phenylbicyclo[2, 2, l]hept-2-yl cation (10) probably by a double Wagner-Meerwein rearrangement involving the intermediacy of 3-methyl-l-phenylbicyclo[3, l, l]hept-2-yl cation (11). The 7, 7-dimethyl-2-phenylbicyclo[2, 2, l]hept 2-yl cation (13) has been generated and shown to rearrange to 5, 5-dimethyl-2-phenylbicyclo[2, 2, l]-hept-2..