NHC carbene supported half-sandwich hydridosilyl complexes of ruthenium: the impact of supporting ligands on Si center dot center dot center dot H interligand interactions

摘要

Reaction of complex CpRu(pyr)(3)PF6 (3) with the NHC carbene IPr (IPr = 1,3-bis(2,6-diisopropylphenyl)-imidazol-2-ylidene) results in the NHC complex Cp(IPr)Ru(pyr)(2)PF6 (4), which was studied by NMR specroscopy and X-ray diffraction analysis. Reaction of Cp(IPr)Ru(pyr)(2)PF6 (4) with LiAlH4 leads to the trihydride Cp(IPr)RuH3 (5) characterised by spectroscopic methods. Heating compound 5 with hydro-silanes gives the dihydrido silyl derivatives Cp(IPr)RuH2(SiR3) (6). Systematic X-ray diffraction studies suggest that complexes 6 have stronger interligand Si center dot center dot center dot H interactions than the isolobal phosphine complexes Cp((Pr3P)-P-i)RuH2(SiR3).