Electrocatalytic Reduction of CO and HO with Zn(II) Complexes Through Metal-Ligand Cooperation.

Air and water-stable zinc (II) complexes of neutral pincer bis(diphenylphosphino)-2,6-di(amino)pyridine ("PNP") ligands are reported. These compounds, [Zn(κ-2,6-{PhPNR}(NCH))Br] (R=Me, 1; R=H, 2), were shown to be capable of electrocatalytic reduction of CO at -2.3 V vs.

Electrocatalytic reduction of CO to CO and HCO with Zn(II) complexes displaying cooperative ligand reduction.

Air-stable zinc(II) pyridyl phosphine complexes, [Zn(κ-2,6-{PhPNMe}(NCH))Br] (1) and [Zn(κ-2-{PhPNMe}(NCH))Br] (2) are reported and 1 was capable of electrocatalytic reduction of CO at -2.3 V Fc to yield CO/HCOH in mixed water/acetonitrile solutions. DFT computations support a proposed mechanism involving electron transfer reactions from a species with the anionic PNP ligand ("L/Zn(II)").

An integrated Re(i) photocatalyst/sensitizer that activates the formation of formic acid from reduction of CO.

The complex cis-[Re(bpy)(CO)]OTf (1OTf) is an integrated photosensitizer/catalyst for the selective visible light promoted photocatalytic reduction of CO. The formation of formic acid is unique among this class of Re catalysts, which yield CO as the selective product. A supplemental photosensitizer, Ru(bpy), considerably enhanced the performance of this catalyst.