Electro-organic reactions. Part 51. Reactivity and stereochemical pathways for cathodically generated radical-anions of α,β-unsaturated ketones in aqueous media

Abstract

The cathodic reduction of α,β-unsaturated ketones in aqueous electrolyte gives efficient C–C coupling with the high stereoselectivity associated with similar reactions in aprotic media. The key features of these reactions are consistent with those expected from the likely mechanism involving water-templated coupling of radical-anions. As a further consequence the stereochemistry of the major products (cyclopentanols and linear hydrodimers) has been unambiguously assigned using X-ray crystallography and 2D NOESY ¹H NMR experiments.