169209 20260223164759.0 doi 10.1016/j.jcat.2026.116721 sideral 148286 ART-2026-148286 eng Poves-Ruiz, Isabel Mechanistic Insights on the β-(Z) alkyne hydrosilylation by a NHC-based Cp*Rh(III) catalyst: from catalyst design to an alternative model for H-Si activation 2026 In-depth studies on the residual hydrosilylation catalytic activity of samples of compound [Cp*RhI {(MeIm)2CH2}]+, bearing an unfunctionalized bis-NHC ligand, lead to the discovery of the excellent catalytic performance of the simple complex [Cp*RhI2(IMe)] (IMe = 1,3-dimethylimidozol-2-ylidene). This compound efficiently catalyzes the hydrosilylation of wide a range of terminal alkynes, with complete regio- and stereoselectivity toward the thermodynamically less stable β-(Z)-vinylsilane isomer. The reaction mechanism has been explored by DFT calculations. The reaction seems to proceed through an ionic outer-sphere mechanism, involving heterolytic activation of the hydrosilane assisted by the rhodium center and a solvent molecule (acetone). In the absence of acetone, a metal–ligand cooperation reaction pathway is proposed, in which the Cp* ligand acts as a proton-relay within the coordination sphere of the Rh(III) center. The cooperative activation of the hydrosilane by the metallocene moiety of the catalyst precursor generates a reactive Rh(I)–silyl intermediate bearing a pentamethylcyclopenta-1,3-diene ligand, [η4 -Cp*H], formed through protonation of the Cp* moiety. Access copy available to the general public Unrestricted info:eu-repo/grantAgreement/ES/DGA/E42-23R info:eu-repo/grantAgreement/ES/MCIU/PID2024-159030NA-I00 info:eu-repo/grantAgreement/ES/MICINN/PID2022-137208NB-I00 info:eu-repo/semantics/openAccess by-nc https://creativecommons.org/licenses/by-nc/4.0/deed.es info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Sánchez-Page, Beatriz (orcid)0000-0001-6675-7450 Jiménez, M. Victoria (orcid)0000-0002-0545-9107 Gallegos, Miguel Munarriz, Julen Universidad de Zaragoza (orcid)0000-0001-6089-6126 Passarelli, Vincenzo (orcid)0000-0002-1735-6439 Pérez-Torrente, Jesús J. Universidad de Zaragoza (orcid)0000-0002-3327-0918 2010 760 Universidad de Zaragoza Dpto. Química Inorgánica Área Química Inorgánica 2012 755 Universidad de Zaragoza Dpto. Química Física Área Química Física 456 (2026), 116721 [13 pp.] J. catal. Journal of Catalysis 0021-9517 2432788 http://zaguan.unizar.es/record/169209/files/texto_completo.pdf Versión publicada 2619212 http://zaguan.unizar.es/record/169209/files/texto_completo.jpg?subformat=icon icon Versión publicada oai:zaguan.unizar.es:169209 articulos driver 2026-02-23-14:54:33 ARTICLE