4399-88-6

Upstream product

• 2154-56-5 benzyl radical 
• 100-39-0 benzyl bromide 
• 100-44-7 benzyl chloride 
• 102-04-5 1,3-Diphenylpropanone 
• 23592-89-4 1-(2-methylphenyl)-3-phenyl-2-propanone 
• 108-88-3 toluene 

Downstream Products

• 3071-34-9 benzyl hydroperoxide 
• 63983-50-6 ascorbic acid radical anion 
• 100-52-7 benzaldehyde 
• 26397-37-5 benzyloxyl 
• 2154-56-5 benzyl radical 
• 13822-09-8 benzyl peroxide 
• 100-51-6 benzyl alcohol 
• 67-56-1 methanol 
• 50-00-0 formaldehyd 
• 2143-68-2 methoxyl radical 

Relevant academic research and scientific papers

Laser flash photolysis and integral equation theory to investigate reactions of dilute solutes with oxygen in supercritical fluids

The absolute reactivity of triplet benzophenone (3BP) and benzyl free radical (PhCH2) toward molecular oxygen (O2) in supercritical CO2 and CHF3 has been measured by laser flash photolysis (LFP). The

Free electron transfer mirrors rotational conformers of substituted aromatics: Reaction of benzyltrimethylsilanes with n-butyl chloride parent radical cations

The rotation motion of a larger substituent of an aromatic ring is accompanied by the electron density fluctuation of the highest occupied molecular orbitals. For benzyltrimethylsilanes p-R3-C 6H4-○-CR1-R2

EPR investigation of persistent radicals produced from the photolysis of dibenzyl ketones adsorbed on ZSM-5 zeolites

Photolysis of ketones (1, 1-oMe, 2, 2-oMe, 3, and 4) adsorbed on ZSM-5 zeolites produces persistent carbon-centered radicals that can be readily observed by conventional steady-state EPR spectroscopy. The radicals are persistent for time periods of seconds to many hours depending on the supramolecular structure of the initial radical@zeolite complex and the diffusion and reaction dynamics of radicals produced by photolysis. The structures of the persistent radicals responsible for the observed EPR spectra are determined by a combination of alternate methods of generation of the same radical, by deuterium substitution, and by spectral simulation. A clear requirement for persistence is that the radicals produced by photolysis must either separate and diffuse from the external to the internal surface or be generated within the internal surface and separate and diffuse apart. The persistence of radicals located on the internal surface is the result of inhibition of radical-radical reactions. Radicals that are produced on the external surface and whose molecular structure prevents diffusion into the internal surface are transient because radical-radical reactions occur rapidly on the external surface. The reactions of the persistent radicals with oxygen and nitric oxide were directly studied in situ by EPR analysis. In the case of reaction with oxygen, persistent peroxy radicals are formed in high yield. The addition of nitric oxide scavenges persistent radicals and leads initially to a diamagnetic nitroso compound, which is transformed into a persistent nitroxide radical by further photolysis. The influence of variation of radical structure on transience/persistence is discussed and correlated with supramolecular structure and reactivity of the radicals and their parent ketones.

Thermal stability of peroxynitrates

Peroxynitrates are thermally unstable intermediates (at ambient temperatures) in the atmospheric degradation of hydrocarbons. In this work, thermal lifetimes of nine peroxynitrates have been measured as a function of temperature and, for two of them, also, as a function of total pressure. In the presence of excess NO, relative concentrations of the peroxynitrates were followed in a 420 I reaction chamber as a function of time by means of long-path IR absorption using a Fourier transform spectrometer. Original data on the unimolecular decomposition rate constants are presented for the peroxynitrates RO2NO2 with R = C6H11, CH3C(O)CH2, C6H5CH2, CH2I, CH3C(O)OC(H)CH3, C6H5OCH2, (CH3)2NC(O), C6H5OC(O), and C2H5C(O). Thermal lifetimes at room temperature and atmospheric pressure are very short (in the order of seconds) for substituted methyl peroxynitrates (i.e., R′CH2O2NO2) but rather long for substituted formyl peroxynitrates (i.e., R″C(O)O2NO2). Kinetic data from this and previous work from our laboratory are used to derive structure-stability relationships which allow an estimate of the thermal lifetimes of peroxynitrates from readily available 13C n.m.r. shift data.

Quenching of singlet oxygen by oxygen- and sulfur-centered radicals: Evidence for energy transfer to peroxyl radicals in solution

Quenching of singlet oxygen luminescence at 1.27 μm by PhS., PhSO., and peroxyl radicals PhOO., t-BuOO., PhCH2OO., Ph2CHOO. and Ph3COO. was studied in liquid solution. The quantum yields of decomposition of different initiators which lead to the formation of free radicals were measured by using nanosecond transient absorption. This allowed determination of singlet oxygen O2(1Δ(g)) quenching rate constants by the radicals. They are 8 M-1 s-1 for the sulfur-centered radicals and (2-7) x 109 M-1 s-1 for peroxyl radicals in acetonitrile. The rapid quenching is attributed to energy transfer quenching by the peroxyls, which have an n → π* transition leading to a low-lying 2A' state above their 2A'' ground state. PhSO. is shown computationally not to have such a low-lying 2A' state. There may be a very low-lying 2B1 state, for PhS., but it is apparently not an efficient acceptor of electronic energy from O2(1Δ(g)).

The Formation of Gas Phase Benzyl Radicals during the Reaction of Toluene and Nitrous Oxide over Li-MgO and Sr-La2O3 Coupling Catalysts

Surface-generated gas-phase benzyl radicals have been detected during the reaction of toluene and nitrous oxide over Li-MgO and Sr-La2O3 catalysts.

Study of the kinetics and equilibrium of the benzyl-radical association reaction with molecular oxygen

The forward rate constant, k1, and the equilibrium constant, Kp, for the association reaction of the benzyl radical with oxygen have been determined. The rate constant k1 was measured as a function of temperature (between 298 and 398 K) and pressure (at 20 and 760 torr of N2) by two different techniques, argon-lamp flash photolysis and excimer-laser flash photolysis, both of which employed UV absorption spectroscopy (at 253 nm and 305 nm, respectively) to monitor the benzyl radical concentration. Over the range of conditions studied, we find that the reaction is independent of pressure and is almost independent of temperature, which is in accord with two early studies of the reaction but in apparent disagreement with more recent work. For our results in 760 torr of N2 and for 298 1 = (7.6 ± 2.4) × 10-13 exp[(190 ± 160)K/T] cm3 molecule-1 s-1. With the flash-photolysis technique, we determined Kp over the temperature range 398-525 K. Experimental values were analyzed alone and combined with theoretically determined entropy values of the benzyl and benzylperoxy radicals to determine the enthalpy of reaction: ΔH°298 = (-91.4 ± 4) kJ mol-1. Previous work on the benzyl radical enthalpy of formation allows us to calculate ΔH°f 298 (Benzylperoxy) = (117 ± 6) kJ mol-1. In addition, we carried out an RRKM calculation of k1 using as constraints the thermodynamic information gained by the study of Kp. We find that all the studies of the association reaction are in good agreement once a fall-off effect is taken into account for the most recent work conducted at pressures near 1 torr of helium.

The Nucleophilicity of Superoxide towards Different Alkyl Halides Estimated from Kinetic Measurements

Values of the rate constant ksub are measured for the substitution reaction between superoxide O2 anion-radical and the alkyl halides butyl chloride, 2-butyl chloride, benzyl chloride, ethyl bromide, butyl bromide, 2-butyl bromide, neopentyl bromide, benzyl bromide, (1-bromo-2,2-dimethylpropyl)benzene and 1-iodoadamantane.These rate constants are compared with the expected rate constant kET for the electron transfer reaction between the same alkyl halides and an aromatic anion radical A anion-radical with the same standard oxidation potential as O2 anion-radical.The ksub/kET ratios show that the mechanism of the substitution reaction amy shift from SN2-like to ET-like on changes in the steric hindrance and the acceptor ability of the alkyl halide.The influence on ksub/kET of the difference in self-exchange reorganization energy λ(0) between O2 anion-radical/O2 and A anion-radical/A is discussed.

Kinetics and thermochemistry of the reaction of benzyl radical with O2: investigations by discharge flow/laser induced fluorescence between 393 and 433 K

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

Rate Constants for Reduction of substituted Methylperoxyl Radicals by Ascorbate Ions and N,N,N',N'-tetramethyl-p-phenylenediamine

Absolute rate constants (k) for reduction of substituted methylperoxyl radicals by ascorbate ions and by TMPD (N,N,N',N'-tetramethyl-p-phenylenediamine) in aqueous solutions have been determined by pulse radiolysis.The rate constants vary from 1E6 to 1E9 M-1 s-1, increasing as the electron-withdraving capacity of the substituent on the peroxyl group increases.Linear correlations are observed between log k and the Taft substituents ?* for a wide variety of substituents, but not all substituents fit the same line.In the case of ascorbate as reductant, the points for peroxyl radicals that contain halogens on the α-carbon lie on a different line (ρ*=0.41) than that for the other substituents (ρ*=1.25).In the case of TMPD there are alsotwo families of peroxyl radicals: Those comprimising the electron-donating groups Me through t-Bu (ρ=5.6) and those containing electron-withdrawing substituents (ρ*=0.64).