Photoreaction of Hexacarbonylmolybdenum(O) and Tricarbonyl(eta(5)-cyclopentadienyl)hydridomolybdenum(II) in the Presence of Cyclopentadiene: Substitution, Oxidative Addition, and Hydrometallation.

摘要

Irradiation of Mo(CO)6 in the presence of C5H6 yields (Eta(5)-C5H5)(Eta(3)-C5H7)-Mo(CO)2 via a sequence of light-induced reactions involving substitution, Mo(CO)(n)(C5H6) (n = 5,4); oxidative addition, (Eta(5)-C5H5)Mo(CO)3H; and hydrometallation, (Eta(5)-C5H5)(Eta(3)-C5H7)Mo(CO)2. The sequence of events can be followed by monitoring the infrared spectral changes in the CO stretching region. An authentic sample of (Eta(5)-C5H5)Mo(CO)3H cleanly yields (Eta(5)-C5H5)(Eta(3)-C5H7)Mo(CO)2 when irradiated in the presence of C5H6; the 355 nm quantum yield for this reaction is 0.12 + or - 0.02. Photoinduced hydrometallation of C5(CH3)5H, trans-trans-2,4-hexadiene, 1,4-pentadiene, trans-1,3-pentadiene also appears to obtain upon irradiation of (Eta(5)-C5H5)Mo(CO)3H in the presence of the diene. Irradiation of Cr(CO)6 in the presence of C5H6 yields Cr(CO)2(Eta(5)-C5H5)(Eta(3)-C5H7). (Author)