Silicon−Hydrogen Bond Activation and Formation of Silane Complexes Using a Cationic Rhodium(III) Complex

Addition of triphenylsilane, trimethylsilane, or triethylsilane to [Cp*(PMe 3 )Rh(Me)(CH 2 Cl 2 )]BAr‘ 4 ( 4 ), a cationic Rh(III) complex, resulted in Si−H bond activation and release of methane below −80 °C. The rare, nonclassical silane complexes [Cp*(PMe 3 )Rh((C 6 H 4 )(η 2 -HSiPh 2 ))]BAr‘ 4 ( 6 ), [Cp*(PMe 3 )Rh(SiMe 3 )(η 2 -HSiMe 3 )]BAr‘ 4 ( 9 ), and [Cp*(PMe 3 )Rh(SiEt 3 )(η 2 -HSiEt 3 )]BAr‘ 4 ( 11 ) have been generated and characterized by NMR spectroscopy. Of note was the presence of 29 Si satellites of the hydride resonances of each of these compounds and large 1 J Si - H coupling constants (56−84 Hz), diagnostic of the presence of η 2 -silane ligands.