Cationic Iridium(I) Complexes as Catalysts for the Alcoholysis of Silanes

The syntheses of five cationic iridium(I) complexes, containing the bidentate ligands bis(1-pyrazolyl)methane (BPM) and bis(3,5-dimethyl-1-pyrazolyl)methane (dmBPM), {[Ir(BPM)(COD)]⁺(BPh₄)^-} (1), {[Ir(dmBPM)(COD)]⁺(BPh₄)^-} (2), {[Ir(BPM)(COD)]⁺[Ir(COD)Cl₂]^-} (4), {[Ir(BPM)(CO)₂]⁺(BPh₄)^-} (3), and {[Ir(dmBPM)(CO)₂]⁺(BPh₄)^-} (5), are reported. The complexes were characterized by NMR spectroscopy, and the solid-state structure of {[Ir(BPM)(CO)₂]⁺(BPh₄)^-} (3) was determined by single-crystal X-ray crystallographic analysis. The complexes {[Ir(BPM)(CO)₂]⁺(BPh₄)^-} (3) and {[Ir(dmBPM)(CO)₂]⁺(BPh₄)^-} (5) are effective catalysts for the alcoholysis of a range of alcohols and hydrosilanes, including secondary and tertiary hydrosilanes, under mild conditions.