Selective Transfer Hydrogenation of C=O and Conjugated C=C Bonds Using An NHC-Based Pincer (CNC)Mn Complex in Methanol.

Base metal catalyzed transfer hydrogenation reactions using methanol is highly challenging. Employing a single N-heterocyclic carbene (NHC)-based pincer (CNC)Mn complex, chemoselective single and double transfer hydrogenation of α, β-unsaturated ketones to saturated ketones or alcohols by utilizing methanol as the hydrogen source is disclosed. The protocol was tolerant towards the selective transfer hydrogenation of C=C or C=O bonds in the presence of several other reducible functional groups and led to the synthesis of several biologically relevant molecules and natural products.