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.
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.
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.
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.
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
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Geiseler,Herrmann
, p. 736,746, 749 (1970)
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Ultraviolet Absorption Spectra of the CH2Cl and CHCl2 Radicals and the Kinetics of their Self-recombination Reactions from 273 to 686 K
Roussel, Pascal B.,Lightfoot, Philip D.,Caralp, Francoise,Catoire, Valery,Lesclaux, Robert,Forst, Wendell
, p. 2367 - 2377 (1991)
The UV absorption spectra of the chloromethyl (CH2Cl) and dichloromethyl (CHCl2) radicals have been determined between 197.5 and 230 nm, together with the absolute rate constants for their association reactions: CH2Cl + CH2Cl -> products (1a), CHCl2 + CHCl2 -> products (1b) as a function of temperature from 273 to 686 K and between 29 and 760 Torr N2 total pressure.The transient decays of the radicals were monitored by time-resolved UV absorption following the flash photolysis of Cl2 mixed with the parent molecules (CH3Cl or CH2Cl2).At a resolution of 2 nm, no vibrational structure was detected in either spectrum which both appear as strong broad electronic bands with maxima around 200 nm (CH2Cl) and 215 nm (CHCl2).At these wavelengths the absolute absorption cross-sections were measured as (1.45 +/- 0.16) x 10-17 and (1.34 +/- 0.24) x 10-17 cm2 molecule-1, respectively, relative to that of CH3O2 at 240 nm (4.55 x 10-18 cm2 molecule-1).The experimental results, supported by RRKM calculations, demonstrate that the measured rate constants for removal of the radicals correspond to the high-pressure limiting rate constants for recombination, both of which exhibit a negative temperature dependence, represented by the following expressions: CH2Cl: k1a = (2.8 +/- 0.3) x 10-11 (T/298)-(0.85 +/- 0.14) cm3 molecule-1 s-1.CHCl2: k1b = (9.3 +/- 1.7) x 10-12 (T/298)-(0.74 +/- 0.10) cm3 molecule-1 s-1.Errors are 1?.The present results are compared to existing data on the self-recombination reactions of the CH3 and CCl3 radicals; the negative temperature dependence of the self-association rate constants for the series CH3, CH2Cl, CHCl2 and CCl3 are shown to be consistent within the framework of a recently developed variational transition-state theory method.
Reactions of N-Pentafluorosulfanylurethanes and Thiolurethanes with Phosphorus Pentachloride
Thrasher, Joseph S.,Clifford, Alan F.
, p. 593 - 596 (1983)
Urethanes of the type SF5NHC(O)OR react with PCl5 to give primarily SF5NCO.In only one case, where R = C6H5, was any evidence for an imine product observed.The corresponding reactions of SF5NHC(O)SR compounds give both SF5NCO and the imine product.The new compounds SF5N=C(Cl)SCH3 and SF5N=C(Cl)SC6H5 were identified by IR, NMR, and mass spectrometry.
Gas-Phase Reactions of Atomic Chlorine with Vinyl Chloride
Iyer, R. Subramonia,Rowland, F. S.
, p. 3730 - 3737 (1985)
The reactions of chlorine atoms with CH2=CHCl have been investigated over the pressure range from 70 to 4000 torr by using radioactive (38)Cl atoms formed by neutron irradiation of CClF3.The only observed product when CH2=CHCl is the sole substrate is CH2=CH(38)Cl in yields varying from 1.35percent at 4000 torr to 44.2percent at 71-torr total pressure.With HI present as a second substrate, CH2ClCH2(38)Cl is observed as a major product with a yield as high as 78percent at 4000-torr total pressure, and CH3CHCl(38)Cl is also found in yields of 2percent or less.A 1,2-chlorine atom migration is required in the overall mechanism, and two quite different kinetic schemes fit the observed yields of CH2=CH(38)Cl and CH2ClCH2(38)Cl very satisfactorily.The favored mechanism involves little initial preference for addition to the CH2 or CHCl ends of CH2=CHCl.The yields of CH2ClCH2(38)Cl at high pressures are proceded by a 1,2-chlorine atom migration from collisionally stabilized CH2CHCl(38)Cl radicals to form CH2(38)ClCHCl or CH2ClCH(38)Cl prior to abstraction of H from HI to form CH2ClCH2(38)Cl.The absolute reaction rate for (38)Cl with CH2=CHCl has been estimated from its relative rate vs. reaction with HI to be about 1.5 X 10E-10 cm3 molecule-1s-1.The energy barriers for chlorine atom addition to either end of CH2=CHCl are no larger than a few hundred cal/mol, and the loss of chlorine atoms from excited CH2(38)ClCHCl* or CH2CHCl(38)Cl* radicals must also have barriers in the exit channels no larger than a few hundred cal/mol.
From 1,2-dialkoxyalkanes to 1,4-dioxanes. A transformation mediated by NbCl5via multiple C-O bond cleavage at room temperature
Marchetti, Fabio,Pampaloni, Guido,Zacchini, Stefano
, p. 3651 - 3653 (2008)
The formation of 1,4-dioxanes and alkyl chlorides from the reactions of polyethers (dme, diglyme, 1,2-diethoxyethane, 1,2-dimethoxypropane) with NbCl5 at room temperature is described; as far as dme is concerned, the reaction mainly occurs in two steps, consisting of (i) cleavage of one O-CH3 bond, followed by (ii) cleavage of the second O-CH3 bond and one of the two O-CH2 linkages. The characterization of intermediate complexes and the isolation of NbOCl3(dme) are reported. The Royal Society of Chemistry.
Laser-Initiated Chain Reactions and Microexplosions in Solid Solutions of Simple Alkenes and Chlorine
Tague, Thomas J.,Kligmann, Peter M.,Collier, C. Patrick,Ovchinnikov, Mikhail A.,Wight, Charles A.
, p. 1288 - 1293 (1992)
Solid-state photochlorination reactions of ethene and propene have been initiated by pulsed ultraviolet laser photolysis.Quantum yields and product branching ratios have been determined by Fourier transform infrared spectroscopy.At 48 K, the photochemical quantum yield for the ethene/Cl2 system is 116 +/- 15.The reaction forms predominantly the anti conformer of 1,2-dichloroethane.At 50K, the propene/Cl2 system yields the largest quantum yields reported to date in the solid state, 740 +/- 120; the anti conformer of 1,2-dichloropropane is the predominant product in this case.At 10K, the reactions of both systems are characterized by a sudden burst of reactivity (a microexplosion) after exposure to a cumulative laser fluence of only 0.9 mJ/cm2 at 337 nm.As much as 67percent of the reactants are converted to products during the microexplosion.A new technique has been developed which utilizes microexplosions for determining relative IR band intensities for conformational isomers in the solid state.
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Weber,Hennion,Vogt
, p. 1458 (1939)
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Single-stage oxychlorination of ethanol to ethylene dichloride using a dual-catalyst bed
Al-Hajri, Rashid,Chadwick, David
, p. 96 - 101 (2010)
The direct production of ethylene dichloride, EDC, from ethanol over a dual-catalyst bed consisting of a zeolite pre-bed and a CuCl2-NaCl/ γ-Al2O3 oxychlorination catalyst has been shown to give greater than 80% yield of EDC with ethyl chloride as the main by-product. The effects of temperature, HCl/air ratio and space velocity were investigated. The most effective zeolite was ZSM-5. It is concluded that the main route to EDC was via ethyl chloride and its oxychlorination and disproportionation.
Photochlorination of Chloroethane and Chloroethane-d5
Tschuikow-Roux, E.,Yano, T.,Niedzielski, J.
, p. 1408 - 1414 (1984)
The hydrogen/deuterium abstraction from C2H5Cl and C2D5Cl by ground-state chlorine atoms has been investigated between 8 and 94 deg C.Results from the internal competition in chloroethane and chloroethane-d5 combined with the results of external competition with CH4 as the reference reaction have yielded rate constant data for the following reactions: CH3CH2Cl + Cl -> CH3CHCl + HCl, k2s; CH3CH2Cl + Cl -> CH2CH2Cl + HCl, k2p; CD3CD2Cl + Cl -> CD3CDCl + DCl, k2s,D; CD3CDCl + Cl -> CD2CD2Cl + DCl, k2p,D.The temperature dependence of the rate constants (cm3s-1) is given by k2s = (1.43 +/- 0.29) X 1E-11 exp, k2p = (1.35 +/- 0.28) X 1E-11 exp, k2s,D = (0.72 +/- 0.14) X 1E-11 exp , and k2p,D = (0.60 +/- 0.12) X 1E-11 exp.The results confirm the general trend of chlorine atom attack being faster at the substituted carbon atom.Kinetic isotope effects for the abstraction of primary and secondary hydrogen are kH/kD = 5.8 and 2.0 at 298 K, respectively.The magnitude of these relatively weak isotope effects agrees with expectations based on other exothermic chlorination reactions and suggests that in the temperature range of the investigation tunneling does not play an important role.
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Mack
, p. 4993 (1967)
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Preparation of high quality ethephon using domestic diester bis-(2-chloroethyl)-2-chloroethylphosphonate as substrate
Zhang, Wenlong,Sun, Dequn
, p. 6463 - 6464 (2013)
Ethephon has been widely used globally. However, few companies can manufacture high quality ethephon with content of 90% in China mainland. This work described a practical procedure, which utilizing bis-(2-chloroethyl)-2- chloroethylphosphonate 2 produced by local Chinese companies as substrate to prepare ethephon with content of over 90 % and high yield.
Application of Time-Resolved Infrared Spectroscopy to the Determination of Absolute Rate Constants for Cl + C2H6 and Cl + C2H5Cl
Kaiser, E. W.,Rimai, L.,Schwab, E.,Lim, E. C.
, p. 303 - 306 (1992)
Time-resolved infrared spectroscopy (TRISP) has been used to determine at 700 Torr and 298 K the absolute rate constants of reactions (1) Cl + C2H6 = C2H5 + HCl 1 = 7.05 (+/-1.4)*10-11 cm3/molecule s> and (2) Cl + C2H5Cl = C2H4Cl + HCl 2 = 6.8 (+/-1.4)*10-12 cm3/molecule s>.Pulsed UV laser photolysis of Cl2 in flowing mixtures of Cl2, C2H6 (or C2H5Cl), and air initiated the reaction.Absolute rate constants were measured by observing the rate of HCl production using this pulsed, broad-band IR technique for time delays from 50 ns to 10 μs after the photolysis laser pulse.Because chain propagation occurs via reactions (4) C2H5 + Cl2 = C2H5Cl + Cl or (6) C2H4Cl + Cl2 = C2H4Cl2 + Cl, corrections for these reactions were included in the absolute rate calculations.A determination of the rate constant of reaction 6 relative to reaction 5, C2H4Cl + O2 = C2H4ClO2, was required to calculate k2.The ratio k6/k5 was measured at 700 Torr by continuous UV photolysis of Cl2, O2, and C2H5Cl mixtures in a static reactor using the relative rate technique.Values of k6/k5 = 0.42 (+/-0.06) and 0.63 (+/-0.15) were obtained for 1-chloroethyl and 2-chloroethyl radicals, respectively.The measured value of k1 agrees with previous low-pressure (10 Torr) determinations verifying that reaction 1 is pressure independent.
Preserved in a Shell: High-Performance Graphene-Confined Ruthenium Nanoparticles in Acetylene Hydrochlorination
Kaiser, Selina K.,Lin, Ronghe,Krumeich, Frank,Safonova, Olga V.,Pérez-Ramírez, Javier
, p. 12297 - 12304 (2019)
The potential implementation of ruthenium-based catalysts in polyvinyl chloride production via acetylene hydrochlorination is hindered by their inferior activity and stability compared to gold-based systems, despite their 4-fold lower price. Combining in-depth characterization and kinetic analysis we reveal the superior activity of ruthenium nanoparticles with an optimal size of 1.5 nm hosted on nitrogen-doped carbon (NC) and identify their deactivation modes: 1) nanoparticle redispersion into inactive single atoms and 2) coke formation at the metal sites. Tuning the density of the NC carrier enables a catalytic encapsulation of the ruthenium nanoparticles into single layer graphene shells at 1073 K that prevent the undesired metal redispersion. Finally, we show that feeding O2 during acetylene hydrochlorination limits coke formation over the nanodesigned ruthenium catalyst, while the graphene layer is preserved, resulting in a stability increase of 20 times, thus rivalling the performance of gold-based systems.
Influence of regeneration conditions on the activity of the catalyst for oxidative chlorination of ethylene
Kurta,Mykytyn,Khaber
, p. 1088 - 1092 (2005)
The possibility of thermochemical regeneration of an industrial batch of a spent and partially deactivated catalyst to improve its activity and selectivity in oxidative chlorination of ethylene to give 1,2-dichloroethane was studied.
Unimolecular Rate Constants for Chemically Activated 1,1,1-Trifluoro-2-chloroethane: A Competitive Three-Channel System
Rakestraw, David, J.,Holmes, Bert E.
, p. 3968 - 3975 (1991)
Chemically activated CF3CH2Cl was prepared with 97.5 kcal/mol of internal energy by the combination of CF3 and CH2Cl radicals.The total unimolecular decomposition rate constant was measured by using two internal standard methods and the average was (7.5 +/- 2.61.5) * 106 s-1.The rate constant for four-centered elimination of HF was measured as (2.8 +/- 0.1) * 106 s-1, for C-Cl bond homolysis the rate constant was (0.8 +/- 5.60.1) * 106 s-1, and by difference the three-centered HCl elimination rate constant was (3.9 +/- 2.63.0) * 106 s-1.These rate constants were compared to predictions from RRKM theory, and threshold energies were assigned for loss of HF (76 kcal/mol), for C-Cl-bond rupture (83 kcal/mol), and for HCl elimination (72 kcal/mol).Product distributions from three activation methods (chemical, multiphoton laser, and thermal) were analyzed to develop a self-consistent view of this complex reaction system.
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Setser
, p. 582 (1968)
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Deactivation factor of CuCl2-KCl/Al2O3 catalyst for ethylene oxychlorination in a commercial-scale plant
Ohashi, Tomokazu,Someya, Sae,Mori, Yoshihiko,Asakawa, Tetsuo,Hanaya, Makoto,Oguri, Motohiro,Watanabe, Ryo,Fukuhara, Choji
, (2020)
Ethylene oxychlorination over a CuCl2-KCl/Al2O3 catalyst was examined for 2 consecutive years in a commercial-scale plant. The oxychlorination performance of the CuCl2-KCl/Al2O3 catalyst deteriorated gradually, which could seriously affect stable operation. To clarify such deactivation factors, the relationship between catalyst performance and physicochemical property change was investigated using X-ray fluorescence, electron probe microanalysis, and Brunauer–Emmett–Teller measurements. Sublimation of the CuCl component and subsequent increment of the ratio of K to Cu components were observed at the inlet of the catalyst bed, and were determined to be contributing factors in the deactivation of the CuCl2-KCl/Al2O3 catalyst.
Method of Converting a Brominated Hydrocarbon to a Chlorinated Hydrocarbon
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Paragraph 0174-0177, (2021/02/19)
The present invention provides a method of converting a brominated hydrocarbon to a chlorinated hydrocarbon that involves contacting together the brominated hydrocarbon and a chlorinated ion exchange resin that has a water content of less than or equal to 30 percent by weight, based on the total weight of the chlorinated ion exchange resin and the water. The brominated hydrocarbon includes at least one replaceable bromo group, where each replaceable bromo group is independently covalently bonded to an sp3 hybridized carbon. Contact between the brominated hydrocarbon and the chlorinated ion exchange resin results in replacement of at least one replaceable bromo group of the brominated hydrocarbon with a chloro group, and correspondingly conversion of at least a portion of the brominated hydrocarbon to the chlorinated hydrocarbon.