A molybdenum–Schiff base complex, a new molecular electro-catalyst for generating hydrogen from acetic acid or water

•Reaction of ligand, H2L and MoCl5 gives a Mo(VI) complex [MoL(O)2] 1.•Structure of 1 is determined by single crystal X-ray diffraction analysis.•Complex 1 can catalyze hydrogen evolution from acetic acid and water.•Sustained catalysis occurs over a 72 h period and no decomposition of 1.

Reaction of 2-pyridylamino-N,N-bis(2-methylene-4-methoxy-6-tert-butylphenol) (H2L) and MoCl5 gives a Mo(VI) complex [MoL(O)2] 1, which has been determined by X-ray crystallography. Electrochemical studies show that complex 1 can catalyze hydrogen evolution from acetic acid with a turnover frequency (TOF) of 39 (DMF) mol/h at an overpotential of 642 mV and from water with a TOF of 360 (pH 7.0) mol/h at an overpotential of 907 mV. Sustained proton reduction catalysis occurs at glassy carbon (GC) electrode from water to give H2 over a 72 h electrolysis period and no observable decomposition of the catalyst.

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