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Synthesis of a Redox-Active NNP-Type Pincer Ligand and Its Application to Electrocatalytic CO₂ Reduction With First-Row Transition Metal Complexes.

ABSTRACT: We report the synthesis of a rigid phosphine-substituted, redox-active pincer ligand and its application to electrocatalytic CO₂ reduction with first-row transition metal complexes. The tridentate ligand was prepared by Stille coupling of 2,8-dibromoquinoline and 2-(tributylstannyl)pyridine, followed by a palladium-catalyzed cross-coupling with HPPh₂. Complexes were synthesized from a variety of metal precursors and characterized by NMR, high-resolution mass spectrometry, elemental analysis, and cyclic voltammetry. Formation of bis-chelated metal complexes, rather than mono-chelated complexes, was favored in all synthetic conditions explored. The complexes were assessed for their ability to mediate electrocatalytic CO₂ reduction, where the cobalt complex was found to have the best activity for CO₂-to-CO conversion in the presence of water as an added proton source.

SUBMITTER: Talukdar K

PROVIDER: S-EPMC6536570 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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