The stereochemistry of quaternisation of 2-methyl-2-azabicyclo[2,2,2]-oct-5-ene and 1,2-dimethyl-1,2,3,6-tetrahydropyridine with trideuteriomethyl iodide

Abstract

Quaternisation of 2-methyl-2-azabicyclo[2,2,2]oct-5-ene (I) and 1,2-dimethyl-1,2,3,6-tetrahydropyridine (II) with trideuteriomethyl iodide in ether proceeds with low stereoselectivity, the double bond having little effect on the preferred steric course of quaternisation. This is probably generally true for quaternisation of 1,2,3,6-tetrahydro-pyridines.