title: Diverse Reactivity of ECp* (E = Al, Ga) toward Low-Coordinate Transition Metal Amides [TM(N(SiMe3)2)2] (TM = Fe, Co, Zn): Insertion, Cp* Transfer, and Orthometalation.
abstract: The reactivity of the carbenoid group 13 metal ligands ECp* (E = Al, Ga) toward low valent transition metal complexes [TM(btsa)2] (TM = Fe, Co, Zn; btsa = bis(trimethylsilyl)amide) was investigated, revealing entirely different reaction patterns for E = Al and Ga. Treatment of [Co(btsa)2] with AlCp* yields [Cp*Co(μ-H)(Al(κ2-(CH2SiMe2)NSiMe3)(btsa))] (1) featuring an unusual heterometallic bicyclic structure that results from the insertion of AlCp* into the TM-N bond with concomitant ligand rearrangement including C-H activation at one amide ligand. For [Fe(btsa)2], complete ligand exchange gives FeCp*2, irrespective of the employed stoichiometric ratio of the reactants. In contrast, treatment of [TM(btsa)2] (TM = Fe, Co) with GaCp* forms the 1:1 and 1:2 adducts [(GaCp*)Co(btsa)2] (2) and [(GaCp*)2Fe(btsa)2] (3), respectively. The tendency of AlCp* to undergo Cp* transfer to the TM center appears to be dependent on the nature of the TM center: For [Zn(btsa)2], no Cp* transfer is observed on reaction with AlCp*; instead, the insertion product [Zn(Al(η2-Cp*)(btsa))2] (4) is formed. In the reaction of [Co(btsa)2] with the trivalent [Cp*AlH2], transfer of the amide ligands without further ligand rearrangement is observed, leading to [Co(μ-H)4(Al(η2-Cp*)(btsa))2] (5).
authors.affiliation: Chair of Inorganic and Metal-Organic Chemistry, Technical University of Munich , D-85748 Garching, Germany.
authors.forename: Jana
authors.initials: J
authors.lastname: Weßing
authors.affiliation: Inorganic Chemistry II, University Bayreuth , D- 95440 Bayreuth, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Göbel
authors.affiliation: Inorganic Chemistry II, University Bayreuth , D- 95440 Bayreuth, Germany.
authors.forename: Birgit
authors.identifier: http://orcid.org/0000-0002-9861-9447
authors.initials: B
authors.lastname: Weber
authors.affiliation: Chair of Inorganic and Metal-Organic Chemistry, Technical University of Munich , D-85748 Garching, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Gemel
authors.affiliation: Chair of Inorganic and Metal-Organic Chemistry, Technical University of Munich , D-85748 Garching, Germany.
authors.forename: Roland A
authors.identifier: http://orcid.org/0000-0002-7532-5286
authors.initials: RA
authors.lastname: Fischer