Reduction of imines via titanium-catalyzed hydromagnesation

Article abstract of DOI:10.1016/S0040-4039(97)01797-8

We have recently discovered that imines can be reduced to amines via a titanium catalyzed hydromagnesation reaction. These reactions employ n-BuMgCl (1.2 eq) as the stoichiometric reducing agent and Cp₂TiCl₂ (3-5 mol%) as a catalyst. Reactions are run under nitrogen at ambient temperature and pressure. For most aldimine and cyclic ketimine substrates amine products are obtained in yields ranging from 69-94%. The reaction is not tolerant of bulky nitrogen substituents or primary enolizable protons on the imine substrate.