A well-defined NHC-Ir(III) catalyst for the silylation of aromatic C-H bonds: Substrate survey and mechanistic insights

Rubio-Pérez, L. ; Iglesias, M. ; Munárriz, J. (Universidad de Zaragoza) ; Polo, V. (Universidad de Zaragoza) ; Passarelli, V. ; Pérez-Torrente, J.J. (Universidad de Zaragoza) ; Oro, L.A. (Universidad de Zaragoza)

Resumen: A well-defined NHC-Ir(iii) catalyst, [Ir(H)2(IPr)(py)3][BF4] (IPr = 1, 3-bis-(2, 6-diisopropylphenyl)imidazol-2-ylidene), that provides access to a wide range of aryl- and heteroaryl-silanes by intermolecular dehydrogenative C-H bond silylation has been prepared and fully characterized. The directed and non-directed functionalisation of C-H bonds has been accomplished successfully using an arene as the limiting reagent and a variety of hydrosilanes in excess, including Et3SiH, Ph2MeSiH, PhMe2SiH, Ph3SiH and (EtO)3SiH. Examples that show unexpected selectivity patterns that stem from the presence of aromatic substituents in hydrosilanes are also presented. The selective bisarylation of bis(hydrosilane)s by directed or non-directed silylation of C-H bonds is also reported herein. Theoretical calculations at the DFT level shed light on the intermediate species in the catalytic cycle and the role played by the ligand system on the Ir(iii)/Ir(i) mechanism.

Idioma: Inglés

DOI: 10.1039/c6sc04899d

Año: 2017

Publicado en: CHEMICAL SCIENCE 8, 7 (2017), 4811-4822
ISSN: 2041-6520

Factor impacto JCR: 9.063 (2017)

Categ. JCR: CHEMISTRY, MULTIDISCIPLINARY rank: 18 / 169 = 0.107 (2017) - Q1 - T1

Factor impacto SCIMAGO: 4.508 - Chemistry (miscellaneous) (Q1)

Financiación: info:eu-repo/grantAgreement/ES/DGA/E07
Financiación: info:eu-repo/grantAgreement/ES/MEC/FPU14-06003
Financiación: info:eu-repo/grantAgreement/ES/MICINN-FEDER/CSD2009-00050
Financiación: info:eu-repo/grantAgreement/ES/MINECO/CTQ2013-42532-P
Financiación: info:eu-repo/grantAgreement/ES/MINECO/CTQ2015-67366-P

Tipo y forma: Article (Published version)

Área (Departamento): Área Química Inorgánica (Dpto. Química Inorgánica)
Área (Departamento): Área Química Física (Dpto. Química Física)