A Surprising Reaction of Trimethylphosphane with the Unsaturated Diruthenium Complex [(η6‐C6Me6)2Ru2(μ2‐H)3]+: Synthesis and Molecular Structure of the Cations [(η6‐C6Me6)Ru2(PMe3)3(μ2‐H)3]+ and [(η6‐C6Me6)2Ru2(PMe3)2(μ2‐H)(H)2]+

Abstract

AbstractWhereas aromatic or aliphatic phosphanes undergo cleavage of the P–C bond in the reaction with [(η6‐C6Me6)2Ru2(μ2‐H)3]+ to give phosphido‐bridged diruthenium cations of the type [(η6‐C6Me6)2Ru2(μ2‐PR2)(μ2‐H)2]+, trimethylphosphane surprisingly yields the substitution product [(η6‐C6Me6)Ru2(PMe3)3(μ2‐H)3]+ (1), as well as the racemic intermediate [(η6‐C6Me6)2Ru2(PMe3)2(μ2‐H)(H)2]+ (2), in the form of the tetrafluoroborate salts. In complex 2, the hydrido ligands are fluxional in solution, as shown by variable‐temperature 1H NMR spectroscopy. Cation 1 reacts with p‐bromothiophenol to give the complex [(η6‐C6Me6)2Ru2(PMe3)3{μ2‐(p‐Br‐C6H4)‐S}(μ2‐H)2]+ (3), isolated as the tetrafluoroborate salt.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)