A comment on the interpretation of 13C n.m.r. δ‐syn‐axial substituent effects in cyclic molecules

Abstract
An alternative explanation for δ‐syn‐axial substituent effects of 13C chemical shifts is given using the concept that the δ‐syn‐axial interaction in the substituted compound replaces the γ‐gauche interaction in the parent molecule. The application of this principle to substituted norbornanes and steroids leads to the conclusion that the ‘net steric’ δ‐syn‐axial shift is upfield rather than downfield.