Base-Promoted, Remote C−H Activation at a Cationic (η5 ‑C5Me5)Ir(III) Center Involving Reversible C−C Bond Formation of Bound C5Me5

C-H bond activation at cationic [(η5-C5Me5)Ir(PMe2Ar')] centers is described, where PMe2Ar' are the terphenyl phosphine ligands PMe2ArXyl2 and PMe2ArDipp2. Different pathways are defined for the conversion of the five-coordinate complexes [(η5-C5Me5)IrCl(PMe2Ar')]+, 2(Xyl)+ and 2(Dipp...

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Detalles Bibliográficos
Autores: Moreno Díaz, Juan José, Fernández Espada-Pastor, María, Campos Manzano, Jesús, López Serrano, Joaquín, Macgregor, Stuart A., Carmona Guzmán, Ernesto
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2019
País:España
Institución:Universidad de Sevilla (US)
Repositorio:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/85662
Acceso en línea:https://hdl.handle.net/11441/85662
https://doi.org/10.1021/jacs.8b11752
Access Level:acceso abierto
Descripción
Sumario:C-H bond activation at cationic [(η5-C5Me5)Ir(PMe2Ar')] centers is described, where PMe2Ar' are the terphenyl phosphine ligands PMe2ArXyl2 and PMe2ArDipp2. Different pathways are defined for the conversion of the five-coordinate complexes [(η5-C5Me5)IrCl(PMe2Ar')]+, 2(Xyl)+ and 2(Dipp)+, into the corresponding pseudoallyls 3(Xyl)+ and 3(Dipp)+. In the absence of an external Brønsted base, electrophilic, remote ζ C-H activation takes place, for which the participation of dicationic species, [(η5-C5Me5)Ir(PMe2Ar')]2+, is proposed. When NEt3 is present, the PMe2ArDipp2 system is shown to proceed via 4(Dipp)+ as an intermediate en route to the thermodynamic, isomeric product 3(Dipp)+. This complex interconversion involves a non-innocent C5Me5 ligand, which participates in C-H and C-C bond formation and cleavage. Remarkably, the conversion of 4(Dipp)+ to 3(Dipp)+ also proceeds in the solid state.