Preparation of Trifluorophosphaneruthenium(II) Complexes from η3:η3-Cyclooctadienediylruthenium(IV) Compounds as Precursors

Abstract

The dinuclear cyclooctadienediylruthenium(IV) compound [{RuCl2(η3:η3-C10H16)}2] (1) reacts with PCy3 in 2-propanol under an H2 atmosphere to give the hydrido(dihydrogen) complex [RuHCl(H2)(PCy3)2] (2) in nearly quantitative yield. Treatment of 1 with PCy3, PiPr3 or PiPr2Ph under argon affords the mononuclear products [RuCl2(η3:η3-C10H16)(PR3)] (3−5) by chloride-bridge cleavage. The corresponding compound 6 with PF3 as phosphane ligand reacts with PCy3 by nucleophilic attack of PCy3 at the carbon atom C3 of the dienediyl chain to give the zwitterionic η2:η3-alkene(allyl)ruthenium(II) complex [RuCl2{η2:η3-CH2=C(Me)−CH(PCy3)(CH2)2CHC(Me)CH2}(PF3)] (7) the crystal and molecular structures of which have been determined. The reaction of 7 with excess PCy3 in the presence of H2 affords the five-coordinate hydrido compound [RuHCl(PF3)(PCy3)2] (8), which upon treatment with acetylene gives the vinyl derivative [RuCl(CH=CH2)(PF3)(PCy3)2] (9). The related cationic carbene complex [RuCl(=CHCH3)(PF3)(PCy3)2]BF4 (10) is obtained by protonation of 9 with HBF4 in ether. (© Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002)