Chemoselective hydrogenation of α,β-unsaturated ketones to allylic alcohols, catalyzed by a mononuclear ruthenium complex containing trans PnBu3 and PPh3 ligands

Ru(CO)2(OAc)2(PnBu3)(PPh3) (OAc = acetate) containing two different trans phosphine ligands, has been employed as pre-catalyst for the chemoselective hydrogenation of α,β-unsaturated ketones to allylic alcohols. Batch catalytic reactions and operando high-pressure NMR experiments have contributed to establish that the hydrogenation of the CO group is performed by the monohydride RuH(CO)2(OAc)(PnBu3)(PPh3).