Synthesis and Characterization of Ir-(κ-NSi) Species Active toward the Solventless Hydrolysis of HSiMe(OSiMe).

The reaction of [IrH(Cl)(κ-NSi)(coe)] () with 1 equiv of PCy (or PHBu) gives the species [IrH(Cl)(κ-NSi)(L)] (L = PCy, ; PHBu, ), which reacts with 1 equiv of AgOTf to afford [IrH(OTf)(κ-NSi)(L)] (L = PCy, and PHBu, ). Complexes , , , and have been characterized by means of NMR spectroscopy and HR-MS. The solid-state structures of complexes , and have been determined by X-ray diffraction studies. The reversible coordination of water to , , and to afford the corresponding adduct [IrH(OTf)(κ-NSi)(L)(HO)] (L = PCy, -HO; PHBu, -HO; coe, -HO) has been demonstrated spectroscopically by NMR studies. The structure of complexes -HO and -HO have been determined by X-ray diffraction studies. Computational analyses of the interaction between neutral [NSi] and [Ir()L(X)] fragments in Ir-NSi species confirm the electron-sharing nature of the Ir-Si bond and the significant role of electrostatics in the interaction between the transition metal fragment and the κ-NSi ligand. The activity of Ir-(κ-NSi) species as catalysts for the hydrolysis of HSiMe(OSiMe) depends on the nature of the ancillary ligands. Thus, while the triflate derivatives are active, the related chloride species show no activity. The best catalytic performance has been obtained when using complexes , with triflate and PCy ligands, as a catalyst precursor, which allows the selective obtention of the corresponding silanol.