title: Intramolecularly stabilised group 10 metal stannyl and stannylene complexes: multi-pathway synthesis and observation of platinum-to-tin alkyl transfer.
abstract: Reaction of [PdClMe(P^N)2] with SnCl2 followed by Cl-abstraction leads to apparent Pd-C bond activation, resulting in methylstannylene species trans-[PdCl{(P^N)2SnClMe}][BF4] (P^N = diaryl phosphino-N-heterocycle). In contrast, reaction of Pt analogues with SnCl2 leads to Pt-Cl bond activation, resulting in methylplatinum species trans-[PtMe{(P^N)2SnCl2}][BF4]. Over time, they isomerise to methylstannylene species, indicating that both kinetic and thermodynamic products can be isolated for Pt, whereas for Pd only methylstannylene complexes are isolated. Oxidative addition of RSnCl3 (R = Me, Bu, Ph) to M(0) precursors (M = Pd or Pt) in the presence of P^N ligands results in diphosphinostannylene pincer complexes trans-[MCl{(P^N)2SnCl(R)}][SnCl4R], which are structurally similar to the products from SnCl2 insertion. This showed that addition of RSnCl3 to M(0) results in formal Sn-Cl bond oxidative addition. A probable pathway of activation of the tin reagents and formation of different products is proposed and the relevancy of the findings for Pd and Pt catalysed processes that use SnCl2 as a co-catalyst is discussed.
authors.affiliation: Organic Chemistry and Catalysis, Debye Institute for Nanomaterial Science, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht (The Netherlands).
authors.forename: Stefan
authors.initials: S
authors.lastname: Warsink
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Derrah
authors.forename: Cornelis A
authors.initials: CA
authors.lastname: Boon
authors.forename: Yves
authors.initials: Y
authors.lastname: Cabon
authors.forename: Jeroen J M
authors.initials: JJ
authors.lastname: de Pater
authors.forename: Martin
authors.initials: M
authors.lastname: Lutz
authors.forename: Robertus J M
authors.initials: RJ
authors.lastname: Klein Gebbink
authors.forename: Berth-Jan
authors.initials: BJ
authors.lastname: Deelman
mesh_terms: D000473:Alkanes / Q000737:chemistry; D000478:Alkylation; D008958:Models, Molecular; D009947:Organotin Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D010165:Palladium / Q000737:chemistry; D010984:Platinum / Q000737:chemistry*; D014001:Tin / Q000737:chemistry*
chemical_list: D000473:Alkanes; D009947:Organotin Compounds; D010984:Platinum; D010165:Palladium; D014001:Tin
keywords: alkyl transfer; metal-metal interactions; palladium; platinum; tin