Articles producció científica> Química Física i Inorgànica

Triazolylidene Iridium Complexes for Highly Efficient and Versatile Transfer Hydrogenation of C=O, C=N, and C=C Bonds and for Acceptorless Alcohol Oxidation

  • Dades identificatives

    Identificador: imarina:4123814
    Autors:
    Mazloomi ZPretorius RPàmies OAlbrecht MDiéguez M
    Resum:
    © 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.
  • Altres:

    Autor segons l'article: Mazloomi Z; Pretorius R; Pàmies O; Albrecht M; Diéguez M
    Departament: Química Física i Inorgànica Química Física i Inorgànica
    Autor/s de la URV: Diéguez Fernández, Montserrat / Pamies Ollé, Oscar
    Paraules clau: Clean water and sanitation
    Resum: © 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.
    Àrees temàtiques: 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
    Accès a la llicència d'ús: https://creativecommons.org/licenses/by/3.0/es/
    ISSN: 00201669
    Adreça de correu electrònic de l'autor: oscar.pamies@urv.cat montserrat.dieguez@urv.cat
    Identificador de l'autor: 0000-0002-2352-8508 0000-0002-8450-0656
    Pàgina final: 11298
    Data d'alta del registre: 2024-11-16
    Volum de revista: 56
    Versió de l'article dipositat: info:eu-repo/semantics/submittedVersion
    Enllaç font original: https://pubs.acs.org/doi/10.1021/acs.inorgchem.7b01707
    URL Document de llicència: https://repositori.urv.cat/ca/proteccio-de-dades/
    Referència a l'article segons font original: Inorganic Chemistry. 56 (18): 11282-11298
    Referència de l'ítem segons les normes 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
    DOI de l'article: 10.1021/acs.inorgchem.7b01707
    Entitat: Universitat Rovira i Virgili
    Any de publicació de la revista: 2017
    Pàgina inicial: 11282
    Tipus de publicació: Journal Publications
  • Paraules clau:

    Chemistry (Miscellaneous),Chemistry, Inorganic & Nuclear,Inorganic Chemistry,Physical and Theoretical Chemistry
    Clean water and sanitation
    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
  • Documents:

  • Cerca a google

    Search to google scholar