Controlling factors determining the regiochemistry of intramolecular alkoxymercuration

Abstract

The intramolecular alkoxymercuration of (E)-5-arylpent-4-en-1-ols indicated that the regioselectivity is closely related to the Hammett constants of the para-substituents on the benzene ring. Large solvent effects on the regioselectivity were also observed. These results were compared with those of the methoxymercuration of β-methylstyrene analogues. The regioselectivity is discussed in terms of steric effects as well as the electronic effects which are suggested by the MO calculation for the mercurinium ion intermediates.