Insight into the Regioselectivity of Nucleophilic Ring‐Opening of Azetidinium Ions Containing Quaternary Carbon Atoms

Abstract

AbstractA set of azetidinium ions each bearing a quaternary carbon atom α to the nitrogen atom were synthesized. These compounds were treated with three different nuclophiles: azide, cyanide and acetate anions. Examination of the regioselectivity in the ring‐opening reactions demonstrated that attack at the quaternary position is intrinsically favored over that at the secondary position. However, these SN2 reactions are highly sensitive to steric crowding, which can counterbalance the natural trend to react at the quaternary carbon.