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RECERCAT author Matheu, Roc author Ertem, Mehmed .Z. author Benet-Buchholz, Jordi author Coronado, Eugenio author Batista, Victor S. author Sala, Xavier author Llobet, Antoni 2018-01-15T16:03:35Z2018-02-15T10:28:33Z2024-04-23T10:32:19Z 2018-01-15T16:03:35Z2018-02-15T10:28:33Z2024-04-23T10:32:19Z 2015 http://hdl.handle.net/2072/305863 https://doi.org/10.1021/jacs.5b06541 We introduce a new family of complexes with the general formula [Run(tda)(py)2]m+ (n = 2, m = 0, 1; n = 3, m = 1, 2+; n = 4, m = 2, 32+), with tda2– being [2,2′:6′,2″-terpyridine]-6,6″-dicarboxylate, including complex [RuIV(OH)(tda-κ-N3O)(py)2]+, 4H+, which we find to be an impressive water oxidation catalyst, formed by hydroxo coordination to 32+ under basic conditions. The complexes are synthesized, isolated, and thoroughly characterized by analytical, spectroscopic (UV–vis, nuclear magnetic resonance, electron paramagnetic resonance), computational, and electrochemical techniques (cyclic voltammetry, differential pulse voltammetry, coulometry), including solid-state monocrystal X-ray diffraction analysis. In oxidation state IV, the Ru center is seven-coordinated and diamagnetic, whereas in oxidation state II, the complex has an unbonded dangling carboxylate and is six-coordinated while still diamagnetic. With oxidation state III, the coordination number is halfway between the coordination of oxidation states II and IV. Species generated in situ have also been characterized by spectroscopic, computational, and electrochemical techniques, together with the related species derived from a different degree of protonation and oxidation states. 4H+ can be generated potentiometrically, or voltammetrically, from 32+, and both coexist in solution. While complex 32+ is not catalytically active, the catalytic performance of complex 4H+ is characterized by the foot of the wave analysis, giving an impressive turnover frequency record of 8000 s–1 at pH 7.0 and 50 000 s–1 at pH 10.0. Density functional theory calculations provide a complete description of the water oxidation catalytic cycle of 4H+, manifesting the key functional role of the dangling carboxylate in lowering the activation free energies that lead to O–O bond formation.     eng Copyright © 2015 American Chemical Society Intramolecular proton transfer boosts water oxidation catalyzed by a Ru complex info:eu-repo/semantics/article URL https://recercat.cat/bitstream/2072/305863/2/181%20Rutda-ms-Repository.pdf File MD5 ca82e060a408efd216310bad5ae82c15 2373446 application/pdf 181 Rutda-ms-Repository.pdf URL https://recercat.cat/bitstream/2072/305863/1/181%20Rutda-ms-Repository.pdf.txt File MD5 1a8ac2cce10a5e3732e307745ab099b2 44022 text/plain 181 Rutda-ms-Repository.pdf.txt