127872 20231023120953.0 doi 10.1002/chem.201502910 sideral 93195 ART-2015-93195 eng Jiménez, M. V. Universidad de Zaragoza (orcid)0000-0002-0545-9107 Oxidation and ß-Alkylation of Alcohols Catalysed by Iridium(I) Complexes with Functionalised N-Heterocyclic Carbene Ligands 2015 The borrowing hydrogen methodology allows for the use of alcohols as alkylating agents for C-C bond forming processes offering significant environmental benefits over traditional approaches. Iridium(I)-cyclooctadiene complexes having a NHC ligand with a O- or N-functionalised wingtip efficiently catalysed the oxidation and ß-alkylation of secondary alcohols with primary alcohols in the presence of a base. The cationic complex Ir(NCCH3)(cod)(MeIm(2- methoxybenzyl))]BF4] (cod=1, 5-cyclooctadiene, MeIm=1-methylimidazolyl) having a rigid O-functionalised wingtip, shows the best catalyst performance in the dehydrogenation of benzyl alcohol in acetone, with an initial turnover frequency (TOF0) of 1283 h-1, and also in the ß-alkylation of 2-propanol with butan-1-ol, which gives a conversion of 94 % in 10 h with a selectivity of 99 % for heptan-2-ol. We have investigated the full reaction mechanism including the dehydrogenation, the cross-aldol condensation and the hydrogenation step by DFT calculations. Interestingly, these studies revealed the participation of the iridium catalyst in the key step leading to the formation of the new C-C bond that involves the reaction of an O-bound enolate generated in the basic medium with the electrophilic aldehyde. Access copy available to the general public Unrestricted info:eu-repo/grantAgreement/ES/MINECO-FEDER/CTQ2013-42532-P info:eu-repo/semantics/openAccess All rights reserved http://www.europeana.eu/rights/rr-f/ 5.771 2015 CHEMISTRY, MULTIDISCIPLINARY 24 / 162 = 0.148 2015 Q1 T1 2.461 2015 Chemistry (miscellaneous) 2015 Q1 info:eu-repo/semantics/article info:eu-repo/semantics/acceptedVersion Fernández-Tornos, J. Modrego, F. J. Universidad de Zaragoza (orcid)0000-0002-9633-3285 Pérez-Torrente, J. J. Universidad de Zaragoza (orcid)0000-0002-3327-0918 Oro, L. A. Universidad de Zaragoza (orcid)0000-0001-7154-7239 2010 760 Universidad de Zaragoza Dpto. Química Inorgánica Área Química Inorgánica 21, 49 (2015), 17877-17889 Chemistry (Weinh.) Chemistry - A European Journal 0947-6539 610794 http://zaguan.unizar.es/record/127872/files/texto_completo.pdf Postprint 2735384 http://zaguan.unizar.es/record/127872/files/texto_completo.jpg?subformat=icon icon Postprint oai:zaguan.unizar.es:127872 articulos driver 2023-10-23-11:02:31 ARTICLE