Kinetic and Stereochemical Outcome of the Titanocene-Promoted Intermolecular Couplings of Epoxides with Nitriles

Abstract

Radical couplings of epoxides and nitriles mediated by Cp2TiCl provide a direct route to the synthesis of β-hydroxyketones. The kinetic and steoreochemical outcome of this reaction is revealed in this paper, revealing the influence of Ti(III) coordination in lowering LUMO energy and enabling effective radical capture. Stereochemical investigations with various epoxide systems demonstrate that steric and electronic effects govern selectivity, generally favoring equatorial addition in cyclohexyl radicals.