title: Effect of a κ1-Bonded-M-1,2,3-triazole (M = Co, Ru) on the Structure and Reactivity of Group 6 Alkoxy (Fischer) Carbenes.
abstract: The [3 + 2] cycloaddition of two different metal-bound azides, [(Me4cyclam)CoII(N3)]ClO4and (η5-C5H5)(dppe)RuII(N3), (dppe = Ph2PCH2CH2PPh2) with Cr(0) and W(0) (ethoxy)(alkynyl) Fischer carbenes has been efficiently used for the preparation of polymetallic metal-carbene complexes. The presence of the κ1-bonded metal triazole causes a significant influence on the electronic properties, structure, and reactivity of this new class of Fischer alkoxycarbenes. For the Ru(II) derivatives, their chemical behavior is considerably influenced by the interaction of the (η5-C5H5)(dppe)RuII-triazole moiety with the empty p-carbene orbital that provokes a noticeable decrease in the electrophilicity of the M═C carbon (manifested by the shielding of the13C NMR chemical shifts). In turn, in the Co(II) derivatives, the incorporation of the (Me4cyclam)CoIImoiety diminishes the aromaticity of the triazole ring and has a marked effect on the energy and distribution of the LUSO orbital, mostly resident on the Co(II) fragment. The almost negligible participation of the carbene moiety in the LUSO makes this position unable to react with nucleophiles. The reactions reported in this work constitute the first examples of [3 + 2] cycloaddition of azides and alkynyl Fischer carbene complexes in solution.
authors.affiliation: Departamento de Química Orgánica I, Facultad de Ciencias Químicas, Universidad Complutense and Centro de Innovación en Química Avanzada (ORFEO-CINQA), 28040 Madrid, Spain.
authors.forename: Elena A
authors.initials: EA
authors.lastname: Giner
authors.affiliation: Departamento de Química Orgánica I, Facultad de Ciencias Químicas, Universidad Complutense and Centro de Innovación en Química Avanzada (ORFEO-CINQA), 28040 Madrid, Spain.
authors.forename: Mar
authors.identifier: http://orcid.org/0000-0002-8961-7685
authors.initials: M
authors.lastname: Gómez-Gallego
authors.affiliation: Departamento de Química Orgánica I, Facultad de Ciencias Químicas, Universidad Complutense and Centro de Innovación en Química Avanzada (ORFEO-CINQA), 28040 Madrid, Spain.
authors.forename: Luis
authors.identifier: http://orcid.org/0000-0002-9054-3118
authors.initials: L
authors.lastname: Casarrubios
authors.affiliation: Instituto de Química Orgánica General, Consejo Superior de Investigaciones Científicas (CSIC) and Centro de Innovación en Química Avanzada (ORFEO-CINQA), Juan de la Cierva 3, 28006, Madrid, Spain.
authors.forename: María C
authors.initials: MC
authors.lastname: de la Torre
authors.affiliation: Departamento de Química Orgánica, Universidad de Valencia and Centro de Innovación en Química Avanzada (ORFEO-CINQA), E-46100, Valencia, Spain.
authors.forename: Carmen
authors.initials: C
authors.lastname: Ramírez de Arellano
authors.affiliation: Departamento de Química Orgánica I, Facultad de Ciencias Químicas, Universidad Complutense and Centro de Innovación en Química Avanzada (ORFEO-CINQA), 28040 Madrid, Spain.
authors.forename: Miguel A
authors.identifier: http://orcid.org/0000-0002-3360-7795
authors.initials: MA
authors.lastname: Sierra