Anomeric effects in aziridin-1-yltetrahydropyrans

Abstract

The stereochemistry of 2-aziridin-1-yltetrahydropyrans has been investigated by n.m.r. spectroscopic and dipole moment studies. Analysis of the 2-H signal, low-temperature n.m.r. data, and dipole moment measurements indicate that the aziridinyl ring is predominantly equatorial in the parent compound whereas the situation is reversed in trans-4-methyl-2-aziridin-1-yltetrahydropyran. Evidence was found for intense shielding above the aziridinyl ring.