F:Flammable;
71-43-2Relevant articles and documents
Tausz,v. Putnoky
, p. 1579 (1919)
Spokes,Gaydon
, p. 1114 (1957)
Glarium,Kraus
, p. 5398,5400 (1950)
Connor et al.
, p. 152 (1955)
Pyrolysis of Styrene. Kinetics and Mechanism of the Equilibrium Styrene Benzene + Acetylene
Grela, M. A.,Amorebieta, V. T.,Colussi, A. J.
, p. 9861 - 9865 (1992)
The thermal unimolecular decomposition of styrene into benzene and acetylene, C6H5CH=CH2 -> C6H6 + HCCH (1), was investigated in a low pressure (ca. 10 mTorr) flow reactor by on-line mass spectrometry between 1180 and 1350 K.Measured rates can be calculated, via RRKM extrapolation, from the expression log (K1, s-1) = 14.38 - 17076/T, which was derived by detailed balance from high-pressure (ca. 50 Torr) low-temperature (878-973 K) kinetic data for the reverse reaction.This value of E1 = 77.9 kcal/mol allows for the generation of vinylidene, H2C=C:; the carbene isomer of acetylene, as a primary product of the title reaction.A non-radical process involving the rate-determining extrusion of H2C=C: from a -7-methylene cyclohepta-2,4-diene intermediate in equilibrium with styrene is consistent with kinetic and thermochemical considerations.
Kinetic Parameters for the Unimolecular Dissociation of Styrene Ion
Dunbar, Robert C.
, p. 3283 - 3286 (1990)
Time-resolved photodissociation measurements of the laser-induced fragmentation of styrene molecular ion have been carried out at 355 nm.Taking thermal energy content into account, a unimolecular dissociation rate of 6.3 * 103 s-1 at an internal energy of 3.66 eV was derived.The new measurement has been combined with previous data from photodissociation and photoionization to give a dissociation rate-energy curve spanning 2 decades of rate values.By RRKM fitting to this curve, unimolecular kinetic parameters E0 = 2.43 +/- 0.05 eV and ΔS% (1000K) = -3.9 +/- 1 cal mol-1 K-1 were derived.The conclusion that this dissociation proceeds through a rate-limiting thight activated complex at E0 = 2.43 eV was affirmed.
Gaeumann,Rayroux
, p. 1563,1568 (1962)
-
Komarewsky
, p. 264 (1957)
-
-
Tuttler,Weissman
, p. 5342 (1958)
-
Heffernon,Jones
, p. 120 (1966)
Kinetic Energy Release in Thermal Ion-Molecule Reactions: Single Charge-Transfer Reactions of V2+ and Ta2+ with Benzene
Gord, James R.,Freiser, Ben S.,Buckner, Steven W.
, p. 8274 - 8279 (1991)
Fourier transform ion cyclotron resonance mass spectrometry (FTICRMS) has been used to study the single charge-transfer reactions of V2+ and Ta2+ with benzene under thermal conditions.Thermal charge-transfer rate constants of 2.0 x 10-9 and 1.2 x 10-9 cm3 molecule-1s-1 were measured for V2+ and Ta2+, respectively.The total kinetic energy of the product ions was determined to be 1.91 +/- 0.50 eV for the V2+ case and 2.82 +/- 0.50 eV for the Ta2+ case.These results and a previous study of the Nb2+ - benzene single charge-transfer system suggest a simple long-distance electron-transfer mechanism proceeding by ionization of the 1a2u orbital of benzene with significant internal excitation of the nascent C6H6+ product.
Chemical nuclear polarization in the oxidation of phenylhydrazine by 1,4- benzoquinone or tetrachloro-1,4-benzoquinone
Levit,Kiprianova,Sterleva,Gragerov
, p. 313 - 316 (1976)
-
Methane chemistry in the hot supersonic nozzle
Somorjai,Kim,Romm
, p. 7025 - 7030 (2001)
The combination of pyrolysis and expansion to a supersonic molecular beam was shown to be very effective in conversion of pure CH4 to heavier hydrocarbons. Pure CH4 conversion reached 70% when it reacted in a hot (1000°-1150°C) supersonic nozzle made of quartz with 100 μ dia orifice. Hydrogen, acetylene, benzene, methyl, and propargyl radicals were the major products in the distribution. CH4 conversion rate was not improved with the addition of O2, NO, or CO2 as O2 reacted primarily with surface carbon formed by CH4 decomposition. No oxygen containing hydrocarbon derivatives were observed. The lifetime of the nozzle was longer than pure CH4 as a reactant resulting from surface carbon removal by oxygen. The mechanism involved pyrolytic rather than catalytic surface generation of free hydrocarbon radicals with subsequent coupling to heavier hydrocarbon products prior to desorption to the gas phase and expansion to the supersonic beam.
Tedder,Vidaud
, p. 81 (1979)
Facile formation of benzene from a novel cyclohexane derivative
Liu, Xiadong,Zhang, Guangtao,Verkade, John G.
, p. 4449 - 4451 (2001)
Upon acidification, benzene forms at room temperature from the novel 1,3,5-cis-trisubstituted cyclohexane wherein the substituents are the azido phosphine cage moieties N3P(MeNCH2CH2)3N. The dominant reaction in the decomposition of this unusually thermally stable intermediate in the presence of HA is the formation of nitrogen and the salt [H2N=P(MeNCH2CH2)3N]A in addition to benzene. Evidence for a transannulated cage intermediate is presented.
Reaction of Hydrogen Atom with Benzene: Kinetics and Mechanism
Nicovich, J. M.,Ravishankara, A. R.
, p. 2534 - 2541 (1984)
The rate coefficients for the reactions H + C6H6 -> products (k1) (1), H + C6D6 -> products (k2) (2), D + C6H6 -> products (k3) (3), and D + C6D6 -> products (k4) (4) have been measured in the temperature range of 298-1000 K by using the pulsed photolysis-resonance fluorescence technique.On the basis of the obtained kinetic information, it is shown that the primary path in all these reactions is addition of the atom to the benzene ring form cyclohexadienyl radical.The rate coefficient for the thermal decomposition of the cyclohexadienyl radical has also been measured.When the rate coefficients for the formation and decomposition of the cyclohexadienyl radical are used, the standard heat of formation of cyclohexadienyl radical at 298 K is calculated to be 45.7 kcal/mol.The measured values of k1-k4 are compared with the results of previous investigations.Most of the observed kinetic behavior in these reactions has been explained on the basis of the addition-decomposition reaction scheme.
Thorp,Kamm
, p. 1022 (1914)
Selective catalytic synthesis of bio-based high value chemical of benzoic acid from xylan with Co2MnO4@MCM-41 catalyst
Fan, Minghui,He, Yuting,Li, Quanxin,Luo, Yuehui,Yang, Mingyu,Zhang, Yanhua,Zhu, Lijuan
, (2021/12/20)
The efficient synthesis of bio-based chemicals using renewable carbon resources is of great significance to promote sustainable chemistry and develop green economy. This work aims to demonstrate that benzoic acid, an important high added value chemical in petrochemical industry, can be selectively synthesized using xylan (a typical model compound of hemicellulose). This novel controllable transformation process was achieved by selective catalytic pyrolysis of xylan and subsequent catalytic oxidation. The highest benzoic acid selectivity of 88.3 % with 90.5 % conversion was obtained using the 10wt%Co2MnO4@MCM-41 catalyst under the optimized reaction conditions (80 °C, 4 h). Based on the study of the model compounds and catalyst's characterizations, the reaction pathways for the catalytic transformation of xylan to bio-based benzoic acid were proposed.
One-step conversion of lignin-derived alkylphenols to light arenes by co-breaking of C-O and C-C bonds
Di, Yali,Li, Guangyu,Li, Zhiqin,Liu, Weiwei,Qiu, Zegang,Ren, Xiaoxiong,Wang, Ying
supporting information, p. 2710 - 2721 (2022/02/21)
The conversion of lignin-derived alkylphenols to light arenes by a one-step reaction is still a challenge. A 'shortcut' route to transform alkylphenols via the co-breaking of C-O and C-C bonds is presented in this paper. The catalytic transformation of 4-ethylphenol in the presence of H2 was used to test the breaking of C-O and C-C bonds. It was found that the conversion of 4-ethylphenol was nearly 100%, and the main products were light arenes (benzene and toluene) and ethylbenzene under the catalysis of Cr2O3/Al2O3. The conversion of 4-ethylphenol and the selectivity of the products were significantly influenced by the reaction temperature. The selectivity for light arenes reached 55.7% and the selectivity for overall arenes was as high as 84.0% under suitable reaction conditions. Such results confirmed that the co-breaking of the C-O and C-C bonds of 4-ethylphenol on a single catalyst by one step was achieved with high efficiency. The adsorption configuration of the 4-ethylphenol molecule on the catalyst played an important role in the breaking of the C-O and C-C bonds. Two special adsorption configurations of 4-ethylphenol, including a parallel adsorption and a vertical adsorption, might exist in the reaction process, as revealed by DFT calculations. They were related to the breaking of C-O and C-C bonds, respectively. A path for the hydrogenation reaction of 4-ethylphenol on Cr2O3/Al2O3 was proposed. Furthermore, the co-breaking of the C-O and C-C bonds was also achieved in the hydrogenation reactions of several alkylphenols. This journal is
