Hiroshi. Ogino

Thermal reactions of alkyl(hydrido)(hydrosilyl)iridium(III) complexes: generation of a hydrido(silylene)iridium(I) species via the reductive elimination of alkane and 1,2-H-shift from the silicon atom to the Ir(I) metal center

Abstract Heating of alkyl(hydrido)(hydrosilyl)iridium(III) complexes LnIr(R)(H) [Ln={η2-MesHSi(CH2)2PPh2}(PMe3)2, Mes=2,4,6-C6H2Me3, R=Me, Et] led to the reductive elimination of alkane. Subsequently, the resulting hydrosilyliridium(I) intermediate LnIr (A) activated the intramolecular carbon–hydrogen bond to give Ir(H){η3-CH2C6H2(CH3)2SiH(CH2)2PPh2}(PMe3)2. In the presence of MeOH, A was quickly trapped with MeOH to give a methoxysilyliridium(III) complex Ir(H)2{η2-Mes(MeO)Si(CH2)2PPh2}(PMe3)2. This reactivity of A with MeOH clearly supports the occurrence of a 1,2-H-shift from the silyl silicon atom to the iridium center to generate a hydrido(silylene)iridium(I) species Ir(H)[η2-{=SiMes(CH2)2PPh2}](PMe3)2.