70460-14-9Relevant academic research and scientific papers
Photochemistry of iron and ruthenium carbonyl complexes: Evidence for light-induced loss of carbon monoxide and reductive elimination of triethylsilane from cis-mer-HM(SiEt3)(CO)3(PPh3)
Liu, David K.,Brinkley, Cynthia G.,Wrighton, Mark S.
, p. 1449 - 1457 (2008/10/08)
The near-UV photochemistry of M(CO)4PPh3 and HM(SiEt3)(CO)3(PPh3) (M = Fe, Ru) has been investigated. The HM(SiEt3)(CO)3(PPh3) complexes have a meridional structure with the H cis to both PPh3 and the SiEt3 and are referred to as the cis-mer isomer. In low-temperature (～100 K) rigid organic glasses the M(CO)4PPh3 undergoes dissociative loss of CO to form the 16-electron M(CO)3PPh3, M-(CO)3(PPh3)(2-MeTHF), M(CO)3(PPh3)(1-C5H10), or cis-mer- and fac-HM(SiEt3)(CO)3(PPh3) complex when the organic glass is an alkane, 2-MeTHF, 1-C5H10, or Et3SiH, respectively. The fac-HM(SiEt3)(CO)3(PPh3) complexes undergo thermal isomerization to the cis-mer isomer upon warmup to 298 K. Near-UV excitation of cis-mer-HM(SiEt3)(CO)3(PPh3) at ～100 K in an organic glass gives evidence for both the loss of CO and reductive elimination of Et3SiH. Photochemistry of the complexes at 298 K in fluid solution accords well with photoreactions observed at ～100 K in rigid media. Irradiation of cis-mer-HM(SiEt3) (CO)3(PPh3) in a hydrocarbon solution of Ph3SiH at 298 K results in the formation of cis-mer-HM(SiPh3) (CO)3(PPh3) and Et3SiH with a 313-nm quantum yield of ～0.6. The process is photochemically reversed if the cis-mer-HM(SiPh3) (CO)3(PPh3) is irradiated in the presence of excess Et3SiH. Irradiation of cis-mer-HM-(SiEt3)(CO)3(PPh3) in a hydrocarbon solution at 298 K in the presence of 13CO yields both 13CO-enriched M(CO)4PPh3 and 13CO-enriched cis-mer-HM(SiEt3)(CO)3(PPh3). Irradiation of cis-mer-HM(SiR3)-(CO)3(PPh3) (R = OMe, OEt) or cis-mer-HRu(SiMeCl2)(CO)3(PPh3) at 298 K in the presence of Et3SiH yields cis-mer-HM(SiEt3)(CO)3(PPh3), establishing the light-induced reductive elimination of R3SiH to occur for a wide range of R groups for these complexes.
