119587 20230622083322.0 doi 10.1039/d1dt01946e sideral 125856 ART-2021-125856 eng Karatas M.O. Iridium(i) complexes bearing hemilabile coumarin-functionalised N-heterocyclic carbene ligands with application as alkyne hydrosilylation catalysts 2021 Access copy available to the general public Unrestricted A set of iridium(i) complexes of formula IrCl(¿C, ¿2-IRCouR')(cod) or IrCl(¿C, ¿2-BzIRCouR')(cod) (cod = 1, 5-cyclooctadiene; Cou = coumarin; I = imidazolin-2-carbene; BzI = benzimidazolin-2-carbene) have beeen prepared from the corresponding azolium salt and [Ir(µ-OMe)(cod)]2 in THF at room temperature. The crystalline structures of 4b and 5b show a distorted trigonal bipyramidal configuration in the solid state with a coordinated coumarin moiety. In contrast, an equilibrium between this pentacoordinated structure and the related square planar isomer is observed in solution as a consequence of the hemilability of the pyrone ring. Characterization of both species by NMR was achieved at the low and high temperature limits, respectively. In addition, the thermodynamic parameters of the equilibrium, ¿HR and ¿SR, were obtained by VT 1H NMR spectroscopy and fall in the range 22-33 kJ mol-1 and 72-113 J mol-1 K-1, respectively. Carbonylation of IrCl(¿C, ¿2-BzITolCou7, 8-Me2)(cod) resulted in the formation of a bis-CO derivative showing no hemilabile behaviour. The newly synthesised complexes efficiently catalyze the hydrosilylation of alkynes at room temperature with a preference for the ß-(Z) vinylsilane isomer. © The Royal Society of Chemistry. info:eu-repo/grantAgreement/ES/DGA-FSE/E42-20R info:eu-repo/grantAgreement/ES/MICINN-FEDER/PID2019-103965GB-I00 info:eu-repo/semantics/openAccess All rights reserved http://www.europeana.eu/rights/rr-f/ 4.569 2021 CHEMISTRY, INORGANIC & NUCLEAR 7 / 46 = 0.152 2021 Q1 T1 0.864 2021 Inorganic Chemistry 2021 Q1 info:eu-repo/semantics/article info:eu-repo/semantics/acceptedVersion Alici B. Passarelli V. Universidad de Zaragoza (orcid)0000-0002-1735-6439 Özdemir I. Pérez-Torrente J.J. Universidad de Zaragoza (orcid)0000-0002-3327-0918 Castarlenas R. (orcid)0000-0003-4460-8678 2010 760 Universidad de Zaragoza Dpto. Química Inorgánica Área Química Inorgánica 50, 32 (2021), 11206-11215 Dalton Trans. Dalton Transactions 1477-9226 1737611 http://zaguan.unizar.es/record/119587/files/texto_completo.pdf Postprint 2623871 http://zaguan.unizar.es/record/119587/files/texto_completo.jpg?subformat=icon icon Postprint oai:zaguan.unizar.es:119587 articulos driver 2023-06-21-15:03:14 ARTICLE