Selective Production of Hydrogen and Lactate from Glycerol Dehydrogenation Catalyzed by a Ruthenium PN3P Pincer Complex

In the quest for cheap and abundant feedstocks for sustainable hydrogen production, glycerol is emerging as a cost-effective, promising liquid organic hydrogen-rich carrier (LOHC) that can be catalytically activated to produce hydrogen alongside valuable organic products. Selective catalytic acceptorless dehydrogenation of glycerol to lactate and hydrogen gas was achieved with a maximum turnover number (TONmax) of ca. 1600, using a pincer-type ruthenium(II) complex bearing a bis(aminophosphine)pyridine PN3P ligand as a homogeneous catalyst under moderate reaction conditions (24 h, 140 °C) in the presence of KOH as base. NMR experiments and DFT calculations provided insights into key steps of the catalytic process and the energetics of the proposed reaction pathway.