F:Flammable;
107-06-2Relevant articles and documents
Transformations of dichloromethane radicals in alkaline water solutions
Kosobutskii,Vrublevskii
, p. 475 - 479 (2002)
Among transformation products of CHCl2 and CH 2Cl radicals generated by γ-irradiation of deaerated water solutions of dichloromethane oxygen-containing compounds (formic acid, formaldehyde, carbon monoxide) and chloride ions were found. The radicals CHCl2 suffer nucleophilic substitution by hydroxyl ions affording anion-radicals HCOO-2 that further transform into formic acid. At the growing concentration of alkali the frequency of chlorine substitution with hydroxyl ions in the dichloromethane radicals increases, and their transformation process becomes a chain reaction.
Tunneling dynamics and spatial correlations of long chain growth in solid-state photochlorination of ethylene at low temperatures
Misochko, E. Ya.,Wight, C. A.,Vetoshkin, E. V.,Benderskii, V. A.
, p. 648 - 662 (1993)
A novel method is described for preparing reactive cryocrystals by deposition of argon-diluted reactant beams and subsequent crystallization during evaporation of the inert gas.Photochlorination of equimolecular ethylene-chlorine mixtures obtained by this method and studied by means of kinetic UV- and IR-spectroscopy reveals activationless chain growth with mean length 300 units in the temperature range 17-45 K.Mean chain lengths greater than 100 are observed up to the conversion degree of 0.6-0.7.Comparison of the experimental data with computer simulations shows that the tunneling reaction is due to the formation of a closely packed reaction complex with high amplitudes of zero-point vibrations which lower the reaction barrier.The commensurability of reactant and product crystal lattices results in linear propagation of chains without accumulation of deformation strain.The chain termination mechanism associated with the spatial correlations of chains is discussed.
Abstraction Reactions of Methylene with Deuterated Methyl Halides
Lee, Peter S.-T.,Rowland, F. S.
, p. 3243 - 3249 (1980)
Tritiated methylene from the 3130-Angstroem photolysis of ketene-t has been reacted with unscavenged deuterated methyl halides (CD3X with X=F, Cl, Br, I) in the gas phase.The distribution of tritium among the products indicates that the reaction of CHT with CD3X often proceeds by halogen abstraction (X=Cl, Br, I) to form CHTX and CD3.The fractional yields of the radioactive products from recombination of such radicals are too large to originate solely from 3CHT reactions, and they imply therefore that most or all of this reaction must be initiated by singlet methylene, as in the following reaction: 1CHT + CD3X --> CHTX + CD3.No halogen abstraction is observed from ketene-t photolysis in the presence of CD3F.The tritiated ethylenes formed in these systems have been analyzed for deuterium content and show measurable quantities of C2H2DT, C2HD2T, and C2D3T.The monodeuterio compound C2H2DT cannot be formed from a direct methylene/ methyl halide reaction, but instead requires a methylene / methyl reaction such as the following : 3CH2 + CHDT --> CH2CHDT* - H --> CH2=CDT.THe 3CH2 (and 3CHT) radicals must react very slowly with CD3X in order to survive for milliseconds without chemical reaction.
Kinetics of the reactions of chlorine atoms with C2H4 (k1) and C2H2 (k2): A determination of ΔHf,298° for C2H3
Kaiser,Wallington
, p. 4111 - 4119 (1996)
The rate constant (k1) for the reaction of Cl atoms with C2H4 has been measured as a function of pressure (0.2-100 Torr) at 297 K using the relative rate technique in two reactors with either FTIR or GC analysis. The results of these and previous experiments (100-3000 Torr) can be described to within ±10% by a Tree expression with the limiting rate constants k1(∞) = (3.2 ± 0.15) × 10-10 cm3 molecule-1 s-1; and k1(0) = (1.42 ± 0.05) × 10-29 cm6 molecule-2 s-1 using Fcent = 0.6. The stated uncertainties are statistical only, and the true uncertainties in the limiting rate constants must include uncertainty in Fcent. Temperature-dependent (297-383 K) measurements of k1 were carried out in the low-pressure regime (0.2-2 Torr) yielding the rate constant expression k1(0) = (1.7 ± 0.3) × 10-29(T/298)-3.28 cm3 molecule-1 s-1. The rate constant, k1b, for the abstraction channel of reaction 1 to form the vinyl radical was determined at 300, 343, and 383 K. This measurement of k1b in combination with literature values of k-1b allows a determination of the heat of formation of the vinyl radical by the third law method [ΔHf,298o(C2H3) = 70.6 ± 0.4 kcal/mol]. Using the same data with the second law yields ΔHf,298o(C2H3) = 69.6 ± 1.6 kcal/mol. These measurements agree satisfactorily with a recent negative-ion photoelectron spectroscopy determination of this quantity (71.6 ± 0.8 kcal mol-1). The pressure dependence of the rate constant (k2) for the reaction of Cl with C2H2 was determined over the range 0.3-700 Torr. The results of these and previous experiments (100-6000 Torr) can be described to within ±10% by a Troe expression with the limiting rate constants k2(∞) = (2.0 ± 0.1) × 10-10 cm3 molecule-1 s-1 and k1(0) = (6.1 ± 0.2) × 10-30 cm6 molecule-2 s-1 using Fcent = 0.6.
Onium Ylide Chemistry. 4. Alkylhalonium Methylides
Olah, George A.,Doggweiler, Hans,Felberg, Jeff D.
, p. 4975 - 4978 (1985)
Alkylhalonium methylides were generated by two independent routes, proving their formation through derived product analysis.The reaction of singlet methylene, produced by photolysis of diazomethane, with methyl and ethyl halides gives in competition with C-H insertion evidence of methylenation of halogen atom, i.e., alkylhalonium methylide formation.The unstable halonium methylides are immediatly protonated or alkylated in the reaction medium to give dialkylhalonium ions which then undergo cleavage to the corresponding alkyl halides.Methyliodonium methylide was also generated via the deprotonation of dimethyliodonium hexafluoroantimonate with sodium hydride in competition with the expected methylation of fluoride and hydride, giving the major products.Subsequent methylation of the methyliodonium methylide by excess dimethyliodonium ion gives methylethyliodonium ion followed by cleavage leading to the formation of ethyl halides and via hydride reduction to ethane, respectively.Attempted formation of alkylhalonium methylides via fluoride cleavage of methylhalonium hexafluoroantimonates was unsuccessful due to ready disproportionation of the halonium ions.
A systematic study on the activation of simple polyethers by MoCl 5 and WCl6
Dolci, Sara,Marchetti, Fabio,Pampaloni, Guido,Zacchini, Stefano
, p. 5367 - 5376 (2010)
MoCl5, 1a, and WCl6, 1b, activate 1,3-dioxolane at room temperature in chlorinated solvents: the compound [MoOCl 3{OC(H)OCH2CH2Cl}]2, 2, has been isolated from MoCl5/dioxolane. The mixed oxo-chloro species WOCl 4, 1c, reacts with 1,3-dioxolane, selectively giving the coordination adduct WOCl4(κ1-C3H6O 2), 3. Dimethoxymethane, CH2(OMe)2, undergoes activation including C-H bond cleavage when reacted with 1a to give the molybdenum complexes [MoOCl3{OC(H)OMe}]2, 4, and Mo 2Cl5(OMe)5, 5. The reactions of 1b with CH 2(OR)2 (R = Me, Et) proceed via O-abstraction with formation of the oxo-derivatives WOCl4[O(R)CH2Cl] (R = Me, 6a; R = Et, 6b) in admixture with equimolar amounts of RCl. The reactions of 1a,b with CMe2(OMe)2 lead to mesityl oxide, MeC(O)CHC(Me)2. A series of simple diethers of general formula ROCH2(CHR′)OR′′ are activated by 1a,b in CDCl 3, usually via cleavage of C-O bonds at high temperature. The complex WCl5(OCH2CH2OMe), 7, has been detected in solution as an intermediate species in the course of the degradation of 1,2-dimethoxyethane (dme) by 1b. The activation of CH(OMe)3 by 1 is limited to C-O bonds and selectively gives methyl chloride and methylformate, which has been found coordinated in WOCl4[OC(H)OMe], 8. The organic fragments produced in the reactions have been detected by GC-MS and NMR analyses, upon hydrolysis of the reaction mixtures. Compounds 2 and 5, which have had their molecular structures ascertained by X-ray diffraction, represent rare examples of crystallographically-characterized dinuclear Mo(v) species containing both halides and oxygen ligands.
NUCLEOPHILIC DISPLACEMENT REACTIONS AT Se(II). REACTION OF ARENESELENENYL CHLORIDES AND 2-CHLOROALKYL PHENYL SELENIDES
Schmid, George H.,Garratt, Dennis G.
, p. 4787 - 4792 (1985)
The products of the title reaction depend upon the relative concentrations of reactants.With equimolar concentrations or an excess of 2-chloroalkyl phenyl selenide, the products are 1,2-dichloroethane and a diaryldiselenide.When excess areneselenenyl chloride is used, the products are a diaryl diselenide and 2-chloroalkyl phenyl selenide dichloride.A mechanism involving nucleophilic displacement at selenenyl selenium is proposed to account for the observed products.Structural changes in the selenide on varying substituents in the 4-position of areneselenenyl chloride has little effect on the rate of the reaction.In the proposed continuum of mechanisms of nucleophilic displacement reactions at Se(II), an SN2-like transition state best accounts for the data.
Nitrogen-Doped Carbon-Assisted One-pot Tandem Reaction for Vinyl Chloride Production via Ethylene Oxychlorination
Chen, De,Chen, Qingjun,Fuglerud, Terje,Ma, Guoyan,Ma, Hongfei,Qi, Yanying,Rout, Kumar R.,Wang, Yalan
, p. 22080 - 22085 (2020)
A bifunctional catalyst comprising CuCl2/Al2O3 and nitrogen-doped carbon was developed for an efficient one-pot ethylene oxychlorination process to produce vinyl chloride monomer (VCM) up to 76 % yield at 250 °C and under ambient pressure, which is higher than the conventional industrial two-step process (≈50 %) in a single pass. In the second bed, active sites containing N-functional groups on the metal-free N-doped carbon catalyzed both ethylene oxychlorination and ethylene dichloride (EDC) dehydrochlorination under the mild conditions. Benefitting from the bifunctionality of the N-doped carbon, VCM formation was intensified by the surface Cl*-looping of EDC dehydrochlorination and ethylene oxychlorination. Both reactions were enhanced by in situ consumption of surface Cl* by oxychlorination, in which Cl* was generated by EDC dehydrochlorination. This work offers a promising alternative pathway to VCM production via ethylene oxychlorination at mild conditions through a single pass reactor.
Thermal degradation of bis (2-chloroethyl) sulfide (mustard gas)
Wagner, George W.,Maciver, Brian K.,Rohrbaugh, Dennis K.,Yang, Yu-Chu
, p. 65 - 76 (1999)
The thermal degradation of mustard gas (ClCH2CH2SCH2CH2Cl, HD ), with and without 5% added water, is examined. GC/MS, LC/MS and NMR were employed to comprehensively analyze the products. After 75 days at 90°C, 91% HD remains (80% with 5% water). After 40 days at 140°C, 30% HD remains (24% with 5% water) and black tar precipitates form. The apparent Ea is 22.4 kcal/mol. Major products include Q (ClCH2CH2SCH2CH2SCH2CH2Cl), 1,2-dichloroethane, polysulfides and 1,4-dithiane. With 5% water, oxygenates such as 1,4-thioxane and 2-chloroethanol are produced as are numerous sulfonium ions, including S-(2-chlorethyl)-1,4-dithianium, a major component of mustard heels. The decomposition does not go to completion due to the equilibrium nature of the reaction at these temperatures.
Partial oxidation of light alkanes by periodate and chloride salts
Kalman, Steven E.,Munz, Dominik,Fortman, George C.,Boaz, Nicholas C.,Groves, John T.,Gunnoe, T. Brent
, p. 5294 - 5298 (2015)
The efficient and selective partial oxidation of light alkanes using potassium periodate and potassium chloride is reported. Yields of methane functionalization in trifluoroacetic acid reach >40% with high selectivity for methyl trifluoroacetate. Periodat
