64315 20200811091507.0 doi 10.1039/c6cy01884j sideral 102757 ART-2016-102757 eng (orcid)0000-0002-0502-7697 Palacios, Laura Mechanistic insight into the pyridine enhanced a-selectivity in alkyne hydrothiolation catalysed by quinolinolate–rhodium(I)–N-heterocyclic carbene complexes 2016 Access copy available to the general public Unrestricted RhI–NHC–olefin complexes bearing a N,O-quinolinolate bidentate ligand have been prepared from [Rh(µ-OH)(NHC)(¿2-olefin)]2 precursors (olefin = cyclooctene, ethylene). The disposition of the chelate ligand with regard to the carbene in the square planar derivatives is strongly influenced by the steric hindrance exerted by the coordinated olefin. These complexes efficiently catalyzed the addition of thiophenol to phenylacetylene with good selectivity to a-vinyl sulfides, which can be increased up to 97% by addition of pyridine. Several key intermediates have been detected including the ¿1-alkenyl species resulting from alkyne insertion into a Rh–H bond. DFT calculations on the mechanism support a hydrometallation pathway that entails the oxidative addition of thiol, 2,1-insertion of the alkyne into the Rh–H bond, and reductive elimination as the rate-determining step. Remarkably, coordination of pyridine to the ß-alkenyl intermediate but not to the a-alkenyl, which results in a net stabilization, is the key for the Markovnikov selectivity. info:eu-repo/grantAgreement/ES/DGA/E07 info:eu-repo/grantAgreement/ES/MINECO/Consolider-Ingenio/CSD2009-0050 info:eu-repo/grantAgreement/ES/MINECO/CTQ2013-42532-P info:eu-repo/semantics/openAccess All rights reserved http://www.europeana.eu/rights/rr-f/ 5.773 2016 CHEMISTRY, PHYSICAL 27 / 145 = 0.186 2016 Q1 T1 1.81 2016 Catalysis 2016 Q1 info:eu-repo/semantics/article info:eu-repo/semantics/acceptedVersion (orcid)0000-0002-3666-5800 Di Giuseppe, Andrea Universidad de Zaragoza Artigas, María José (orcid)0000-0001-5823-7965 Polo, Victor Universidad de Zaragoza (orcid)0000-0001-8054-2237 Lahoz, Fernando J. Universidad de Zaragoza (orcid)0000-0003-4460-8678 Castarlenas, Ricardo Universidad de Zaragoza (orcid)0000-0002-3327-0918 Pérez-Torrente, Jesús J. Universidad de Zaragoza (orcid)0000-0001-7154-7239 Oro, Luis A. Universidad de Zaragoza 2010 760 Universidad de Zaragoza Dpto. Química Inorgánica Área Química Inorgánica 2012 755 Universidad de Zaragoza Dpto. Química Física Área Química Física 6, 24 (2016), 8548-8561 CATALYSIS SCIENCE & TECHNOLOGY Catalysis Science and Technology 2044-4753 1026271 http://zaguan.unizar.es/record/64315/files/texto_completo.pdf Postprint 124690 http://zaguan.unizar.es/record/64315/files/texto_completo.jpg?subformat=icon icon Postprint oai:zaguan.unizar.es:64315 articulos driver 2020-08-11-09:03:13 ARTICLE