Striking Differences in Properties of Geometric Isomers of [Ir(tpy)(ppy)H]+: Experimental and Computational Studies of their Hydricities, Interaction with CO2, and Photochemistry. Issue 47 (2nd October 2015)

• Record Type: Journal Article
• Authors: Garg, Komal; Matsubara, Yasuo; Ertem, Mehmed Z.; Lewandowska‐Andralojc, Anna; Sato, Shunsuke; Szalda, David J.; Muckerman, James T.; Fujita, Etsuko
• Is Part Of: Angewandte Chemie international edition. Volume 54:Issue 47(2015)
• Page Start: 14128
• Page End: 14132
• Publication Date: 2015-10-02
• Subjects: CO2 reduction -- homogeneous catalysis -- hydricity -- iridium hydrides -- photochemistry; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201506961
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: We prepared two geometric isomers of [Ir(tpy)(ppy)H] +, previously proposed as a key intermediate in the photochemical reduction of CO2 to CO, and characterized their notably different ground‐ and excited‐state interactions with CO2 and their hydricities using experimental and computational methods. Only one isomer, C‐trans‐ [Ir(tpy)(ppy)H] +, reacts with CO2 to generate the formato complex in the ground state, consistent with its calculated hydricity. Under photocatalytic conditions in CH3 CN/TEOA, a common reactive C‐trans ‐[Ir(tpy)(ppy)] 0 species, irrespective of the starting isomer or monodentate ligand (such as hydride or Cl), reacts with CO2 and produces CO with the same catalytic efficiency. Abstract : Two geometric isomers of [Ir(tpy)(ppy)H] + were prepared and their ground‐ and excited‐state properties towards reaction with CO2, as well as their hydricities, were characterized using experimental and computational methods.