A facile method for the synthesis of heterobimetallic chloro-bridged complexes containing (R3P)2MCl (M = Pt or Pd) fragments

Abstract

A convenient synthesis of cationic, heterobimetallic complexes of general formulae [(R₃P)₂M¹(µ-Cl)₂M²(chel)]BF₄, [(R₃P)₂M¹(µ-Cl)₂Rh(cod)]BF₄ and [(R₃P)₂M¹(µ-Cl)₂M³(chel)]BF₄ (M¹, M² = Pd^II or Pt^II; M³ = Rh^III or Ir^III, chel = anion of 2-phenylpyridine, benzo[h]quinoline, C₆H₅CHRNMe₂ or η³-allyl) has been elaborated. These complexes were formed in quantitative yields by metathesis reactions of the dicationic complexes [{(R₃P)₂M¹(µ-Cl)}₂][BF₄]₂ with the corresponding neutral, homodimeric compounds [{(cod)Rh(µ-Cl)}₂] and [{(chel)M³(µ-Cl)}₂]. Reactions with half-sandwich complexes such as [{(p-cym)RuCl(µ-Cl)}₂], (cym = cymene), on the other hand, were shown to result in chloride transfer. The structures of [(Bu₃P)₂Pt(µ-Cl)₂Pd(η³-C₃H₅)]BF₄ and [(Bu₃P)₂Pt(µ-Cl)₂Rh(bzq)₂]BF₄ (bzq = benzo[h]quinoline anion) were determined by X-ray diffraction analyses.