Development of efficient molecular catalysts for photocatalytic CO₂ reduction is desirable but challenging. At present, the majority of reported molecular catalysts consist of the transition metal centers coordinated by N-containing ligands. Inspired by the sulfur-containing active site found in carbon monoxide dehydrogenases, we here report a novel Ni-based molecular catalyst bearing 2,6-bis([(2-pyridinylmethyl)thio]methyl) pyridine) as the pentadentate ligand. The product is assessed for photocatalytic CO₂ reduction in acetonitrile/water solution using Ru(bpy)₃Cl₂ as the photosensitizer and triethanolamine as the electron donor. Under the optimal condition, a total of ca. 25 μmol CO is produced after 7 h visible light irradiation with a large turnover number of 63 and high selectivity of 91%.

期望开发有效的用于光催化还原CO _2的分子催化剂，但是具有挑战性。目前，大多数报道的分子催化剂是由含氮配体配位的过渡金属中心组成的。受一氧化碳脱氢酶中含硫活性位点的启发，我们在此报告了一种新型的镍基分子催化剂，其中带有2,6-双（[（2-吡啶基甲基甲基）硫代]甲基）吡啶作为五齿配体。使用Ru（bpy）₃ Cl ₂对产物在乙腈/水溶液中的光催化还原CO ₂进行评估作为光敏剂，三乙醇胺作为电子给体。在最佳条件下，总共约 可见光照射7 h后，产生25μmolCO，其转换数大，为63，选择性高，为91％。