2154-56-5Relevant academic research and scientific papers
TUNNELING PARAMETERS FOR THE HYDROGEN ATOM ABSTRACTION REACTIONS OF DIPHENYLCARBENE IN A LOW TEMPERATURE TOLUENE MATRIX
Wright, Bradford B.,Senthilnathan, V. P.,Platz, Matthew S.,McCurdy, C. W.
, p. 833 - 836 (1982)
Tunneling reaction rate constants of diphenylcarbene in a toluene matrix can be fit by an asymmetric Eckart barrier.The barrier heights are in good agreement with theory.
Dissociation Rate Constants of Alkylbenzenes from Hot Molecules Formed by 158-nm (F2 Laser) Irradiation
Shimada, Tetsuya,Ojima, Yuichi,Nakashima, Nobuaki,Izawa, Yasukazu,Yamanaka, Chiyoe
, p. 6298 - 6302 (1992)
Toluene, p-xylene, deuterated p-xylene, and mesitylene under low-pressure conditions as well as p-xylene under high-pressure conditions were studied with a 158-nm laser.Rise curves of the photoproducts were observed by the method of nanosecond laser photolysis.The ground-state alkylbenzenes with an internal energy of 8 eV are formed by internal conversion following the laser excitation.The alkylbenzenes dissociate to the corresponding benzyl-type and phenyl-type radicals via the hot molecule state.The dissociaton rate constants were 9.3 (+/- 0.7) x 107 s-1, 1.5 (+/- 0.3) x 107 s-1, 4.6 (+/- 0.4) x 106 s-1, and 3.0 (+/- 0.9) x 106 s-1, respectively.Dissociation rate constants of the C-H bond in the methyl group of the alkylbenzenes were estimated from these results and compared with previous predictions.
Nanosecond laser flash photolysis and steady-state photolysis studies of benzyltrimethylsilane and trimethylsilyldiphenylmethane
Hiratsuka, Hiroshi,Kobayashi, Satoshi,Minegishi, Takeshi,Hara, Masaki,Okutsu, Tetsuo,Murakami, Shinji
, p. 9174 - 9183 (1999)
Flourescence measurements and nanosecond laser flash photolysis were carried out to study the photophysical and photochemical processes of benzyltrimethylsilane and trimethylsilyldiphenylmethane at room temperature. A significant solvent effect was observed for the laser flash photolysis of benzyltrimethylene; in methanol, absorption bands due to benzyl-type radicals and the triplet were seen, while only T-T absorption was observed in cyclohexane. No solvent effect was found for the laser flash photolysis of trimethylsilyldiphenylmethane. A transient absorption attributable to the 1,3-trimethylsilyl-shifted intermediate was seen with a lifetime of ca. 27 ms in both solvents, and no absorption band ascribable to diphenylmethyl radicals or the triplet was observed. GC-MS spectra of photoproducts caused by trimethylsilyldiphenylmethane were consistent with the assignment of the transient absorption. Results were explained in terms of the computed molecular structure for the excited singlet states of the molecules using the PM3 method.
Kinetics and thermochemistry of the reaction of benzyl radical with O2: investigations by discharge flow/laser induced fluorescence between 393 and 433 K
Elmaimouni,Minetti,Sawerysyn,Devolder
, p. 399 - 413 (1993)
The kinetics of the reaction of the benzyl radical with molecular oxygen has been studied between 393 and 433 K. The Discharge Flow technique with detection of benzyl radicals by Laser Induced Fluorescence in their visible absorption band has been used. A
MOLECULAR ORBITAL CORRELATION OF ARYLMETHYL CHLORIDE ATOM ABSTRACTION BY STANNYL RADICALS
Soppe-Mbang, Helene,Gleicher, Gerald Jay
, p. 1 - 6 (1980)
A series of monochloromethylated polycyclic benzenoid hydrocarbons have been treated with triphenyltin hydride and AIBN initiator at 70 deg C.Under these conditions the only observable reaction is reduction of the starting materials to methylarenes.A sign
Shock tube determination of the overall rate of NH2 + NO → products in the thermal De-NOx temperature window
Song,Hanson,Bowman,Golden
, p. 715 - 721 (2001)
The rate coefficient of the reaction NH2 + NO → products (R1) was determined in shock tube experiments using frequency-modulation absorption spectroscopy for detection of NH2. Because of the sensitivity of the diagnostic system, very low reactant concentrations could be employed in order to reduce the influence of secondary reactions on the NH2 profiles. Benzylamine, C6H5CH2NH2, was used as a thermal source of the NH2 radicals in the experiments. To determine the reaction rate, a perturbation strategy was employed that is based on changes in the NH2 profiles when NO is added to the C6H5CH2NH2/Ar mixtures. The measured NH2 profiles were interpreted by detailed kinetic modeling to obtain the overall reaction rate of R1 in the temperature range 1262-1726 K. The lower temperature limit of the present study is in the middle of the Thermal De-NOx temperature window. The present rate measurements are consistent with both our previous determination of the rate at higher temperatures and lower temperature data. A rate expression obtained by combining our higher temperature data and lower temperature data is. k1 = 6.83 × 1015 T-1.203 e106/T(K) cm3 mol-1 s-1 for the temperature range 200-2500 K. The estimated uncertainty of the rate coefficient is ±20%.
Fluorescence from samarium(II) iodide and its electron transfer quenching: Dynamics of the reaction of benzyl radicals with Sm(II)
Skene,Scaiano,Cozens
, p. 7918 - 7921 (1996)
The luminescence from SmI2 in THF can be readily quenched by a variety of electron acceptors. In the case of organohalides, the reaction is quite fast; for example, for dichloromethane the rate constant is 2.7 × 108 M-1 s
C-C and C-H Bond Splits of Laser-Excitated Aromatic Molecules. 3. UV Multiphoton Excitation Studies
Hippler, H.,Riehn, Ch.,Troe, J.,Weitzel, K.-M.
, p. 6321 - 6326 (1990)
Parent disappearance and fragment formation yields are measured in the UV multiphoton excitation of cycloheptatriene, toluene, and ethylbenzene.The dependence on laser fluence and bath gas pressure is recorded.The results are interpreted in terms of a com
The Formation of Gas Phase Benzyl Radicals during the Reaction of Toluene and Nitrous Oxide over Li-MgO and Sr-La2O3 Coupling Catalysts
Xu, Mingting,Lunsford, Jack H.
, p. 1203 - 1204 (1995)
Surface-generated gas-phase benzyl radicals have been detected during the reaction of toluene and nitrous oxide over Li-MgO and Sr-La2O3 catalysts.
Photochemical processes of benzyltrimethylsilane at 77 K. Remarkable solvent effects and reaction mechanism
Hiratsuka, Hiroshi,Kadokura, Yukihiro,Chida, Hiroyuki,Tanaka, Mieko,Kobayashi, Satoshi,Okutsu, Tetsuo,Oba, Makoto,Nishiyama, Kozaburo
, p. 3035 - 3041 (1996)
Photophysical and photochemical processes of benzyltrimethylsilane have been studied in 3-methylpentane and ethanol glass at 77 K. Remarkable solvent effects were observed in the UV photolysis: in ethanol glass, benzyl radicals were produced, while in 3-methylpentane glass α-trimethylsilylbenzyl radicals and benzyltrimethylsilane radical cations were produced. It was confirmed that the α-trimethylsilylbenzyl radicals and benzyltrimethylsilane radical cations were formed via the lowest triplet state and the benzyl radicals via the excited singlet state or higher triplet state. The molecular structure of the excited-state benzyltrimethylsilane has been studied by MNDO-PM3 calculations. Based on the results, a possible mechanism involving the excited state of radical pair character has been proposed for the photochemical process of benzyltrimethylsilane.
