Electrochemical reactions. Part XI. Reduction of apoverbenone (6,6-dimethylnorpin-3-en-2-one)

Abstract

In a cyclic voltammetric study of apoverbenone in anhydrous dimethylformamide no indication was obtained of reduction to a stable anion radical at temperatures varying from 298 to 196 K. Electrochemical reduction in aqueous dimethylformamide afforded two diketonic dimers and a small amount of a triketonic trimer. The dimers are stereoisomers formed by the union of two 6,6-dimethyl-4-oxonorpinan-2-yl radicals, the more abundant dimer being formed by union of radicals from the less hindered side. Reduction in anhydrous dimethylformamids gave an isomeric triketonic trimer.