Synthesis, structure, and catalytic behavior of a PSiP pincer-type iridium(III) complex

The synthesis and characterization of a novel cyclometalated Iridium(III) complex [IrCl(H)(PSiP)] containing monoanionic, tridentate coordinating PSiP-pincer ligands [κ3-(2-tBu2PC6H4)2SiMe]− ([PSiP]) is reported. Complex (3) is one of the few examples of bis(phosphino)silyl(hydrido)iridium(III) complexes structurally characterized by single crystal X-ray analysis. This compound has also been shown to catalyze the transfer hydrogenation of ketones to the corresponding secondary alcohols moderately with 2-propanol as the hydrogen source instead of using molecular dihydrogen gas or hazardous reducing agents (e.g., NaBH4 and LiAlH4), and tBuOK as the base.