TY - JOUR
T1 - Unraveling the photochemistry of Fe(CO)5 in solution
T2 - Observation of Fe(CO)3 and the conversion between 3Fe(CO)4 and 1Fe(CO)4(solvent)
AU - Portius, Peter
AU - Yang, Jixin
AU - Sun, Xue Zhong
AU - Grills, David C.
AU - Matousek, Pavel
AU - Parker, Anthony W.
AU - Towrie, Michael
AU - George, Michael W.
PY - 2004/9/1
Y1 - 2004/9/1
N2 - The photochemistry of Fe(CO)5 (5) has been studied in heptane, supercritical (sc) Ar, scXe, and scCH4 using time-resolved infrared spectroscopy (TRIR). 3Fe(CO)4 (34) and Fe(CO)3(solvent) (3) are formed as primary photoproducts within the first few picoseconds. Complex 3 is formed via a single-photon process. In heptane, scCH4, and scXe, 34 decays to form 14·L (L = heptane, CH4, or Xe) as well as reacting with 5 to form Fe2(CO)9. In heptane, 3 reacts with CO to form 14·L. The conversion of 34 to 14·L has been monitored directly for the first time (L = heptane, kobs = 7.8(±0.3) x 107 s-1; scCH4, 5(±1) x 106 s-1; scXe, 2.1(±O.1) x 107 s-1). In scAr, 34 and 3 react with CO to form 5 and 34, respectively. We have determined the rate constant (kCO = 1.2 x 107 dm3 mol -1 s-1) for the reaction of 34 with CO in scAr, and this is very similar to the value obtained previously in the gas phase. Doping the scAr with either Xe or CH4 resulted in 34 reacting with Xe or CH4 to form 14·Xe or 14·CH4. The relative yield, [34]:[3] decreases in the order heptane > scXe > scCH4 ≫ scAr, and pressure-dependent measurements in scAr and scCH4 indicate an influence of the solvent density on this ratio.
AB - The photochemistry of Fe(CO)5 (5) has been studied in heptane, supercritical (sc) Ar, scXe, and scCH4 using time-resolved infrared spectroscopy (TRIR). 3Fe(CO)4 (34) and Fe(CO)3(solvent) (3) are formed as primary photoproducts within the first few picoseconds. Complex 3 is formed via a single-photon process. In heptane, scCH4, and scXe, 34 decays to form 14·L (L = heptane, CH4, or Xe) as well as reacting with 5 to form Fe2(CO)9. In heptane, 3 reacts with CO to form 14·L. The conversion of 34 to 14·L has been monitored directly for the first time (L = heptane, kobs = 7.8(±0.3) x 107 s-1; scCH4, 5(±1) x 106 s-1; scXe, 2.1(±O.1) x 107 s-1). In scAr, 34 and 3 react with CO to form 5 and 34, respectively. We have determined the rate constant (kCO = 1.2 x 107 dm3 mol -1 s-1) for the reaction of 34 with CO in scAr, and this is very similar to the value obtained previously in the gas phase. Doping the scAr with either Xe or CH4 resulted in 34 reacting with Xe or CH4 to form 14·Xe or 14·CH4. The relative yield, [34]:[3] decreases in the order heptane > scXe > scCH4 ≫ scAr, and pressure-dependent measurements in scAr and scCH4 indicate an influence of the solvent density on this ratio.
UR - http://www.scopus.com/inward/record.url?scp=4344631002&partnerID=8YFLogxK
U2 - 10.1021/ja048411t
DO - 10.1021/ja048411t
M3 - Article
C2 - 15327330
AN - SCOPUS:4344631002
SN - 0002-7863
VL - 126
SP - 10713
EP - 10720
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
IS - 34
ER -