Author, as appears in the article.: Mazloomi Z; Pretorius R; Pàmies O; Albrecht M; Diéguez M
Department: Química Física i Inorgànica Química Física i Inorgànica
URV's Author/s: Diéguez Fernández, Montserrat / Pamies Ollé, Oscar
Keywords: Clean water and sanitation
Abstract: © 2017 American Chemical Society. A set of iridium(I) and iridium(III) complexes is reported with triazolylidene ligands that contain pendant benzoxazole, thiazole, and methyl ether groups as potentially chelating donor sites. The bonding mode of these groups was identified by NMR spectroscopy and X-ray structure analysis. The complexes were evaluated as catalyst precursors in transfer hydrogenation and in acceptorless alcohol oxidation. High-valent iridium(III) complexes were identified as the most active precursors for the oxidative alcohol dehydrogenation, while a low-valent iridium(I) complex with a methyl ether functionality was most active in reductive transfer hydrogenation. This catalyst precursor is highly versatile and efficiently hydrogenates ketones, aldehydes, imines, allylic alcohols, and most notably also unpolarized olefins, a notoriously difficult substrate for transfer hydrogenation. Turnover frequencies up to 260 h-1were recorded for olefin hydrogenation, whereas hydrogen transfer to ketones and aldehydes reached maximum turnover frequencies greater than 2000 h-1. Mechanistic investigations using a combination of isotope labeling experiments, kinetic isotope effect measurements, and Hammett parameter correlations indicate that the turnover-limiting step is hydride transfer from the metal to the substrate in transfer hydrogenation, while in alcohol dehydrogenation, the limiting step is substrate coordination to the metal center.
Thematic Areas: Química Physical and theoretical chemistry Medicina i Materiais Interdisciplinar Inorganic chemistry General medicine Farmacia Engenharias iii Engenharias ii Engenharias i Ciências biológicas iii Ciências biológicas ii Ciências biológicas i Ciências agrárias i Chemistry, inorganic & nuclear Chemistry (miscellaneous) Biotecnología Astronomia / física
licence for use: https://creativecommons.org/licenses/by/3.0/es/
ISSN: 00201669
Author's mail: oscar.pamies@urv.cat montserrat.dieguez@urv.cat
Author identifier: 0000-0002-2352-8508 0000-0002-8450-0656
Last page: 11298
Record's date: 2024-11-16
Journal volume: 56
Papper version: info:eu-repo/semantics/submittedVersion
Link to the original source: https://pubs.acs.org/doi/10.1021/acs.inorgchem.7b01707
Licence document URL: https://repositori.urv.cat/ca/proteccio-de-dades/
Papper original source: Inorganic Chemistry. 56 (18): 11282-11298
APA: Mazloomi Z; Pretorius R; Pàmies O; Albrecht M; Diéguez M (2017). Triazolylidene Iridium Complexes for Highly Efficient and Versatile Transfer Hydrogenation of C=O, C=N, and C=C Bonds and for Acceptorless Alcohol Oxidation. Inorganic Chemistry, 56(18), 11282-11298. DOI: 10.1021/acs.inorgchem.7b01707
Article's DOI: 10.1021/acs.inorgchem.7b01707
Entity: Universitat Rovira i Virgili
Journal publication year: 2017
First page: 11282
Publication Type: Journal Publications