71435-61-5Relevant academic research and scientific papers
Synthesis of cationic allyl- and dienecarbonyl complexes of group VI-VIII metals in the presence of strong protonic acid
Krivykh, V. V.,Gusev, O. V.,Rybinskaya, M. I.
, p. 351 - 362 (1989)
Cationic allylcarbonyl complexes of Cr, Mo, W, Mn, Re, Fe, Co, Rh and Ir are synthesized by reaction of a carbonyl-containing compound with allyl alcohol or conjugated diene in the presence of strong protonic acid.This reaction is promoted by an increase in basicity of the initial complex and an increase in acidity of the medium; the nature of the organic substrate is also important for synthesis of this type of carbonyl complex.Cationic diene complexes have been formed by the action of dienes and acid on compounds with a metal-metal bond or on neutral allyl complexes.
A novel facet of carbonyliron-diene photochemistry: The η4-s-trans isomer of the classical Fe(CO)3(η4-s-cis-1,3-butadiene) discovered by time-resolved IR spectroscopy and theoretically examined by density functional methods
Bachler, Vinzenz,Grevels, Friedrich-Wilhelm,Kerpen, Klaus,Olbrich, Gottfried,Schaffner, Kurt
, p. 1696 - 1711 (2008/10/08)
The photolysis of Fe(CO)3(η4-s-cis-1,3-butadiene) (1) and Fe(CO)4(η2-1,3-butadiene) (2), formerly studied in low-temperature matrixes, is reexamined in cyclohexane solution at ambient temperature using time-resolved IR spectroscopy in the v(CO) region. Flash photolysis of 2 (λexc = 308 nm) generates Fe(CO)3(η4-s-trans-1,3-butadiene) (5) as a transient product, which then rearranges to form the classical η4-s-cis-1,3-butadiene complex 1. Species 5, previously addressed as the coordinately unsaturated Fe(CO)3(η2-1,3-butadiene) (3), is also photogenerated from 1, in this case along with the very short-lived CO loss fragment Fe(CO)2(η4-1,3-butadiene) (τ ? = 17.3 kcal·mol-1) with nearly complete recovery of 1. According to density functional calculations at the BP86 level of theory, 5 resides in a distinct energy minimum, 20.3 kcal·mol-1 above 1 and separated from it by a barrier of 15.0 kcal·mol-1. Its computed structure involves a diene dihedral angle of 129°. Species 3 (with a diene dihedral angle of -150.1°), by contrast, is predicted to exist in a rather flat minimum, which makes it too short-lived for detection with our instrumentation. Flash photolysis of Fe(CO)5 generates the very short-lived (3(solv) species in addition to the familiar Fe(CO)4(solv) fragment (τ = 10-15 μs), Fe2(CO)9 being the ultimate product in the absence of potential trapping agents other than CO. Deliberate contamination of the system with water gives rise to the formation of Fe(CO)4(H2O) as a longer lived transient (ca. 1 ms). In the presence of 1,3-butadiene, both 2 and 5 appear almost instantaneously. The latter decays, again in the millisecond time range, with formation of 1, thus providing clear evidence of a single-photon route from Fe(CO)5 to 1 in addition to the established two-photon sequence via the monosubstituted complex 2.
FORMATION OF 1,3-DIENETRICARBONYLIRON COMPLEXES FROM THE REACTION OF DIPOTASSIUM TETRACARBONYLFERRATE WITH ALLYLIC COMPOUNDS
Butsugan, Yasuo,Yamashita, Akihiko,Araki, Shuki
, p. 103 - 108 (2007/10/02)
The reaction of dipotassium tetracarbonylferrate with various allylic phosphates and halides gives 1,3-dienetricarbonyliron complexes.The formation of the complexes is highly stereoselective depending on the geometry of the allylic compounds used.
IR LASER PYROLYSIS AND THE ISOTOPIC LABELLING OF ORGANOMETALLIC COMPOUNDS
Bristow, Neil J.,Moore, Barry D.,Poliakoff, Martyn,Ryott, Graham J.,Turner, James J.
, p. 181 - 188 (2007/10/02)
A homogeneous gas phase pyrolysis technique involving SF6 sensitization and a continuous wave (CW) CO2 laser, is described for preparing small quantities (ca. 100 mg) of organometallic compounds.Several reactions have been successfully carried out and the synthesis of Os(CO)5 from H2Os(CO)4 and CO is discussed in detail.With IR laser pyrolysis, room temperature reactors and sub-atmospheric pressures can be used for reactions which normally require high pressures and temperatures.
Low-temperature matrix photochemistry of (1,3-diene)tricarbonyliron complexes
Ellerhorst, Gabriele,Gerhartz, Wolfgang,Grevels, Friedrich-Wilhelm
, p. 67 - 71 (2008/10/08)
UV photolysis of (η4-2,3-dimethylbutadiene)Fe(CO)3 and (η4-butadiene)Fe(CO)3 in inert matrices at 10 K was monitored by IR and UV spectroscopy. Elimination of CO is the predominant photoreaction. In the latter case we also observed the decomplexation of the butadiene ligand and hence the formation of (η2-butadiene)Fe(CO)3. This product is also obtained during the photolysis of (η2-butadiene)Fe(CO)4 which is subsequently transformed to (η4-butadiene)Fe(CO)3. For comparison, (η2-ethylene)Fe(CO)4 and (η2-1,3-cyclohexadiene)Fe(CO)4 were photolyzed under analogous conditions. Photolysis of (η4-1,3-diene)Fe(CO)3 complexes in nitrogen matrices gives (η4-1,3-diene)Fe(CO)2N2; formation of (η2-butadiene)Fe(CO)3N2 from (η2-butadiene)Fe(CO)4 requires annealing of the nitrogen matrix subsequent to irradiation.
THE USE OF POLYMERS AS MATRICES FOR ORGANOMETALLIC PHOTOCHEMICAL REACTIONS
Paoli, Marco-A. De,Oliveira, Sonia M. De,Galembeck, Fernando
, p. 105 - 110 (2007/10/02)
A matrix technique for the study of photochemical preparation of unstable and air-sensitive organometallic compounds is described.The matrix used is a film of inert polymer, such as polytetrafluorethylene (PTFE).The films containing the compounds can be handled under normal ambient conditions.The method is used to study the products and photochemical reactions of pentacarbonyliron with olefins.
