7393-45-5Relevant academic research and scientific papers
Kinetics of Cyclopropyl Radical Reactions. 1. Absolute Rate Constants for Some Addition and Abstraction Reactions
Johnston, Linda J.,Scaiano, J. C.,Ingold, K. U.
, p. 4877 - 4881 (1984)
The reactions of cyclopropyl radicals produced in the photodecomposition of bis(cyclopropylformyl)peroxide have been examined with the use of laser flash photolysis techniques.For example, the reactions with styrene, β-methylstyrene, 1,4-cyclohexadiene, and carbon tetrachloride have rate constants in benzene at 298 K of (1.5+/-0.3)x107, (2.0+/-0.5)x106, (7.9+/-0.3)x106, and (1.5+/-0.2)x106 M-1 s-1, respectively. in the case of carbon tetrachloride, a study of the temperature dependence of the kinetics (1:4 benzene:CF2ClCFCl2) in the 0 to 68 deg C range yields log (k14/M-1 s-1)=(8.7+/-0.4)-(3.5+/-0.6)/θ, where θ=2.3RT kcal/mol.For addition reactions, the kinetics at 298 K follow the order Ph.>c-C3H5.>RCH2CH2..For H-atom abstractions the reactivities of Ph. and c-C3H5. do not follow a simple relationship, though both are more reactive than RCH2CH2. radicals.
Synthetic method and process of halogenated cyclopropane
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Paragraph 0016, (2021/03/31)
The invention discloses a synthetic method and process of halogenated cyclopropane. The synthesis method and process comprise the following two steps of: (1) reacting cyclopropylamine serving as a rawmaterial with halogenated metal salt in the presence of nitrosation reagents such as nitrous acid ester to obtain 1, 1-dihalogenated cyclopropane; and (2) carrying out metallization reaction on the 1, 1dihalogenated cyclopropane and an organic metal reagent, and hydrolyzing to obtain halogenated cyclopropane. The synthesis method and process have the advantages that toxic reagents causing environmental pollution are not used, the purity and yield of the obtained product are high, and the synthesis method and process are suitable for industrial production.
Kinetics of elementary reactions in the chain chlorination of cyclopropane
Hurley, Michael D.,Schneider, William F.,Wallington, Timothy J.,Mann, David J.,DeSain, John D.,Taatjes, Craig A.
, p. 2003 - 2010 (2007/10/03)
The kinetics of elementary reactions involved in the chain chlorination of cyclopropane were studied using a combination of absolute and relative rate constant measurements and first principles electronic structure calculations. Absolute rate coefficients for the reaction of Cl with cyclopropane were measured between 293 and 623 K by a laser-photolysis/CW infrared absorption method. To support the experimental investigations, first principles electronic structure calculations were performed. Vibrational spectra of c-C3H5Cl, c-C3H4Cl2, and c-C3H3Cl3 were calculated. Gem-C3H4Cl2 is calculated to be the kinetically and thermodynamically most favored dichlorocyclopropane. The computational results were consistent with a model in which gem-C3H4Cl2 is the predominant product of chlorination of C3H5Cl, and gem-C3H3Cl3 is the only product of chlorination of gem-C3H4Cl2. Chlorocyclopropane was ～ a factor of 10 times more reactive than cyclopropane toward chlorine atoms at 296 K and is converted into dichlorocyclopropane.
Photolysis of Matrix-Isolated Cyclopropylidene Ketene: Kinetic and Theoretical Studies of the Cyclopropylidene Formation
Monnier, Maurice,Allouche, Alain,Verlaque, Patrick,Aycard, Jean-Pierre
, p. 5977 - 5985 (2007/10/02)
Cyclopropylidene ketene 2 is generated by ultraviolet irradiation (λ >/= 230 nm) of cyclopropanecarbonyl chloride isolated in argon matrices at 15 K.FT-IR spectra of the primary photolysis products (2 and HCl) trapped in the same cage show the formation o
Solvent pressure effects in free radical reactions. 2. Reconciliation of the gas and condensed phase chlorination of cyclopropane
Tanko, James M.,Suleman, N. Kamrudin
, p. 5162 - 5166 (2007/10/02)
The results reported herein demonstrate that the chemoselectivity (SH2 ring opening vs abstraction of a cyclopropyl hydrogen) associated with the free radical chlorination of cyclopropane is solvent dependent. Internal pressure is implicated as the solvent parameter responsible for the observed solvent effect. (Solvents of high internal pressure favor the SH2 process; hydrogen abstraction becomes more important in solvents of low internal pressure or in the gas phase.) Extrapolation of the solution phase results to zero internal pressure accurately predicts the gas-phase result, suggesting that the difference in chemoselectivity between the vapor- and condensed-phase reactions is attributable to internal pressure in the condensed phase medium. No evidence for the chlorine atom cage effect is found in the chlorination of cyclopropane.
Conformational Selectivity in the Solid-State Photochlorination of Cyclopropane
Tague, Thomas J.,Wight, Charles A.
, p. 3266 - 3269 (2007/10/02)
The solid-state free-radical chain reaction of chlorine with cyclopropane has been investigated with the use of pulsed UV laser photolysis and transmission FTIR spectroscopy.The photochemical quantum yield for an equimolar mixture of the two reagents prepared as a thin film by vapor deposition at 77 K is 52 +/- 8.Samples prepared at this temperature form the anti,anti conformer of 1,3-dichloropropane as the initial reaction product, even when the photolysis is carried out at temperatures as low as 10 K.However, selective formation of the gauche,gauche conformer is observed in the early stages of photolysis for samples that are prepared and photolyzed at 10 K.Continued photolysis of the 10 K sample leads to a sudden burst of reactivity (microexplosion) in which HCl and chlorocyclopropane are formed in addition to distributions of 1,3-dichloropropane conformers.The results indicate that the control of conformational selectivity in this reaction is governed by the influence of temperature and sample density on elementary steps in the reaction mechanism.
INFRARED LASER MULTIPHOTON ABSORPTION AND REACTION OF ORGANIC COMPOUNDS: SYNTHETICALLY UNIQUE REACTION CONTROL
Danen, Wayne C.,Setser, D. W.,Nguyen, Hanh H.,Ibrahim, Md. Sani B.
, p. 173 - 180 (2007/10/02)
Several examples of synthetically unique reaction controll effect by pulsed infrared laser multiphoton irradiation are reviewed.The uniqueness derives from the ability of the pulsed laser to rapidly vibrationally heat molecules coupled with an extremely short reaction time of approximately 10 μs for the processes discussed herein.Three systems are discussed: a bifunctional reactant with competing reaction channels, a reactant with consecutive reaction channels, and the free radical chlorination of cyclopropane.
Bestimmung der Geschwindigkeitskonstanten der Reaktion von 1CH2 mit Fluor- und Chlorethen
Simon, F. G.,Heydtmann, H.
, p. 543 - 545 (2007/10/02)
The rate constants for the addition of 1CH2 to fluoroethene and chloroethene have been determined using the known rate constant for the reaction of 1CH2 with ketene.The experiments yielded the results k4a(296 K) = (8.2 -/+ 0.6)E13 cm3 mol-1 s-1 k4b(296 K) = (2.9 -/+ 0.4)E13 cm3 mol-1 s-1. - Keywords: Chemical Kinetics / Gases / Photochemistry / Radicals
The Addition of t-Butoxy Radicals to Halo-olefins
Cuthbertson, Matthew J.,Rizzardo, Ezio,Solomon, David H.
, p. 315 - 324 (2007/10/02)
A radical trapping technique employing 1,1,3,3-tetramethylisoindolin-2-yloxyl (1) as scavenger has been used to examine the regioselectivity for tail or head addition (kT/kH) by t-butoxy radicals to chloroethylene (5), fluoroethylene (6), 1,1-difluoroethylene (7), and 1,1,2-trifluoroethylene (8) at 30-75 deg C.Addition rates relative to that for ethylene (4) have also been evaluated.An atypical preference for head addition was observed for olefins (7) and (8).In the case of (7) the regioselectivity was shown to vary with temperature according to A comparison of the selectivity with that of other radicals indicates that t-butoxyl exhibits nucleophilic character in its addition to halo-olefins.
