Photochemistry of cobalt carbonyl complexes having a cobalt-silicon bond and its importance in activation of catalysis

Abstract : Photochemistry of R3SiCo(CO)4 (R = Et, Ph) in hydrocarbon solvents shows that the dominant primary excited state process is loss of CO, not cleavage of the Si-Co bond. The 366 nm quantum yield for CO substitution by P(OPh)3 is 0.28 + or - 0.05 to give R3SiCo(CO)3P(OPh)3. Regeneration of catalytic activity in the Co2(CO)8/1-pentene/HSiEt3 system can be accomplished photochemically by exciting the Et3SiCo(CO)4 species.