Tuning the activity and selectivity of iridium-NSiN catalyzed CO₂ hydrosilylation processes

The catalytic activity of various Ir-NSiN-type complexes, containing different ancillary ligands and/or modified NSiN-type ligands, as catalyst precursors for CO₂ hydrosilylation has been studied. The results from these experiments evidenced that the activity and selectivity of the above mentioned catalytic systems depend on the nature of the ancillary ligands as well as on the reaction parameters (temperature and CO₂ pressure). Thus, the best catalytic performance has been achieved at 328 K and 8 bar of CO₂ using the complex [Ir(H)(CF₃CO₂)(NSiN∗)(coe)] (NSiN∗ = fac-bis-(4-methylpyridine-2-yloxy)methylsilyl) as a catalyst precursor.