Xi:Irritant;
110-56-5Relevant articles and documents
Determination of the hydrogen-bond basicity of weak and multifunctional bases: The case of lindane (γ-hexachlorocyclohexane)
Ouvrard, Carole,Lucon, Maryvonne,Graton, Jerome,Berthelot, Michel,Laurence, Christian
, p. 56 - 64 (2004)
We made use of four methods for determining the hydrogen-bond (HB) basicity of lindane (λ-hexachlorocyclohexane): (i) experimental Fourier transform IR measurement of a sum of individual 1:1 equilibrium constants for the formation of 1:1 4-fluorophenol-lindane hydrogen-bonded complexes in CCl4; (ii) calculation of the overall HB basicity from octanol-water partition coefficients; (iii) correlation of the HB basicity of chloroalkanes with the electrostatic potentials around chlorine atoms; and (iv) correlation of the HB basicity of chloroalkanes with the computed enthalpy of their complexes with hydrogen fluoride. It is consistently found that lindane remains a weak HB base because multifunctionality cannot fully compensate for the electron-withdrawing inductive effects that chlorine atoms exert over one another. Actually, only five chlorine atoms behave as HB acceptors, one axial chlorine being deactivated by inductive effects. Stereoelectronic effects lead to the formation of three-centered hydrogen bonds. Copyright
POLAR RADICALS XVIII. ON THE MECHANISM OF CHLORINATION BY N-CHLOROAMINES: INTERMOLECULAR AND INTRAMOLECULAR ABSTRACTION.
Tanner, Dennis D.,Arhart, Richard,Meintzer, Christian P.
, p. 4261 - 4278 (1985)
The photochlorinations of the n-butyl, n-pentyl, and n-hexyltrimethylammonium chlorides, using molecular chlorine in hexachloroacetone or 15percent CD3CO2D/85percent H2SO4, or using N-chlorodimethylamine in the acid solvent are described.The ammonium group exerted a strong polar directing effect upon the site of substitution.This effect was found to be more pronounced in the more polar protic solvent.The reagent, N-chlorodimethylamine, generated the dimethylamminium radical, whose reaction showed a polar sensitivity toward hydrogen abstraction similar to that of the chlorine atom, but exhibiting a much greater secondary/primary selectivity.Comparison of the isomer distributions obtained from the self photochlorination reactions of N-chloro-n-hexylmethylamine and N-chloro-n-pentylmethylamine in the acid solvent, with the distribution pattern obtained for the chlorinations of the ammonium salts with N-chlorodimethylamine, suggested that the self chlorinations of the N-chloroamines proceed by the intramolecular hydrogen abstraction mechanism suggested previously.
Fragmentation of alkoxychlorocarbenes in the gas phase
Blake, Michael E,Jones Jr., Maitland,Zheng, Fengmei,Moss, Robert A
, p. 3069 - 3071 (2002)
In contrast to photolysis or thermal decomposition in solution, which is dominated by ionic reactions, flash vacuum pyrolysis of alkylchlorodiazirines in the gas phase generates radicals. The cyclopropylcarbinyl system is re-examined and the l-norbornylca
Diels-Alder Reactions of Trichlorophosphaethene
Teunissen, Herman T.,Hollebeek, Jan,Nieuwenhuizen, Peter J.,Baar, Ben L. M. van,Kanter, Frans J. J. de,Bickelhaupt, Friedrich
, p. 7439 - 7444 (1995)
The Diels-Alder reactions of trichlorophosphaethene (3), generated in situ from dichloro(dichloromethyl)phosphine (2), with 1-vinylnaphthalene (6), 1-(1-methylethenyl)cyclohexene (4), and 1-cyclohexene (13) at 60-75 deg C, are described.The reactions of 3 with 4 and 6 afforded, after aromatization of the primary Diels-Alder adducts 5 and 8 under the influence of triethylamine, the 2-chlorophosphinines 9 and 11, respectively.The reaction with 13, however, led to the formation of the "double adduct" 16, which could not be isolated in pure form.The formation of the "double adduct" is explained by a subsequent Diels-Alder reaction of 13 with dihydrophosphinine 15, which is formed after HCl elimination from the primary Diels-Alder adduct 14.The reaction of 13 with 23, the pentacarbonyltungsten complex of 2, furnished 27, the pentacarbonyltungsten complex of 16, which was isolated in pure form.The regiochemistry of the Diels-Alder reactions described above is discussed on the basis of MNDO/PM3 calculations of the frontier molecular orbital coefficients.The Diels-Alder reactions proceed with normal electron demand, and the experimentally observed regiochemistry is in accordance with theoretical predictions.The formation of the "double adducts" 16 and 27 is rationalized as a consequence of the high HOMO energy of 13 compared with that of 4.
Solid-phase reactions of alkanedicarboxylic acids with the Pb(OAc) 4-NH4Cl system
Nikishin, Gennady I.,Sokova, Lyubov L.,Makhaev, Viktor D.,Kapustina, Nadezhda I.
, p. 264 - 265 (2003)
The title reactions of HOOC(CH2)nCOOH acids afford α,ω-dichloroalkanes (n = 3, 4, 6) and lactones (n = 3, 4) as the main products.
Ethers as Oxygen Donor and Carbon Source in Non-hydrolytic Sol–Gel: One-Pot, Atom-Economic Synthesis of Mesoporous TiO2–Carbon Nanocomposites
Escamilla-Pérez, Angel Manuel,Louvain, Nicolas,Boury, Bruno,Brun, Nicolas,Mutin, P. Hubert
, p. 4982 - 4990 (2018)
Mesoporous TiO2–carbon nanocomposites were synthesized using an original non-hydrolytic sol–gel (NHSG) route, based on the reaction of simple ethers (diisopropyl ether or tetrahydrofuran) with titanium tetrachloride. In this atom-economic, solvent-free process, the ether acts not only as an oxygen donor but also as the sole carbon source. Increasing the reaction temperature to 180 °C leads to the decomposition of the alkyl chloride by-product and to the formation of hydrocarbon polymers, which are converted to carbon by pyrolysis under argon. The carbon–TiO2 nanocomposites and their TiO2 counterparts (obtained by calcination) were characterized by nitrogen physisorption, XRD, solid state 13C NMR and Raman spectroscopies, SEM, and TEM. The nanocomposites are mesoporous with surface areas of up to 75 m2 g?1 and pore sizes around 10 nm. They are composed of aggregated anatase nanocrystals coated by an amorphous carbon film. Playing on the nature of the ether and on the reaction temperature allows control over the carbon content in the nanocomposites. The nature of the ether also influences the size of the TiO2 crystallites and the morphology of the nanocomposite. To further characterize the carbon coating, the behavior of the carbon-TiO2 nanocomposites and bare TiO2 samples toward lithium insertion–deinsertion was investigated in half-cells. This simple NHSG approach should provide a general method for the synthesis of a wide range of carbon–metal oxide nanocomposites.
Preparation method of dichloroalkane
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Paragraph 0020, (2021/02/10)
The invention discloses a preparation method of dichloroalkane, which comprises the following steps: mixing diol, a catalyst and a solvent, stirring and heating the components, introducing HCl gas into the mixture, and carrying out reflux reaction for 3-5 hours; and after the reaction is finished, treating the reaction solution to obtain dichloroalkane. According to the preparation method providedby the invention, the catalyst ammonium chloride is added, so that the reaction speed is obviously increased, and side reactions are reduced. In the invention, a large amount of solvent water is added in the reaction process, so that on one hand, the formation of monochloro ether by-products can be effectively inhibited, a water phase can be directly and repeatedly used, and basically no sewage is discharged; besides, by using the oil-water separator, the dichloroalkane product can be effectively separated, the product purity is high, and the yield is high.
Continuous method for preparation of dihalogenated alkane from diol compound
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Paragraph 0051-0054; 0069-0075, (2020/03/16)
The invention discloses a continuous method for preparation of dihalogenated alkane from a diol compound. A diol compound and haloid acid are used as the substrate, a microchannel reactor is utilizedto synthesize dihalogenated alkane continuously. Synthesis of the dihalogenated alkane includes the steps of: inputting the diol compound and haloid acid into a mixer respectively by a metering pump at room temperature, conducting premixing, then sending the mixture into a high-temperature section of the microchannel reactor at for reaction, and controlling the reaction temperature by an externalcirculating heat exchange system; at the end of the reaction, letting the product flow out from an outlet of the microchannel reactor and enter a cooling section, letting the cooled material enter a liquid separation kettle for standing and liquid separation, and collecting an organic layer; and preheating the organic layer, then feeding the preheated organic layer into a rectifying tower by a metering pump, controlling the temperature and reflux ratio of a reboiler, and collecting fractions at a specific temperature, thus obtaining the target product in a product collecting tank. The method provided by the invention has the characteristics of high reaction efficiency, safety, environmental protection, convenience and rapidity.
Quinoline derivatives and its preparation method and in the application of neural protection in
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Paragraph 0024-0027, (2019/02/19)
The invention discloses a quinoline derivative and its preparation method and in the application of neural protection in, quinoline derivatives of the formula is Wherein R1 , R2 , R3 , R4 Independently selected from - H, - F or - OCH3 . Anti-A β25 - 35 Induced PC12 cell protective action of injury the experimental results show that, in the dosage is 100μmol/L under the condition of, KL201, KL202 and KL208 with the survival rate of the model set of differences are statistical significance (p25 - 35 Induced neurotoxicity, obviously improve the survival rate of the cells, with nerve protection function, can be used as neuroprotective agents for more in-depth research.
1,4-dichlorobutane production technology
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Paragraph 0026-0036, (2019/10/23)
The invention provides a 1,4-dichlorobutane production technology. The technology comprises the following steps: 1, preparing 1,4-butanediol, triphosgene, a catalyst and a reaction kettle with an elevated tank, wherein a molar ratio of the 1,4-butanediol to triphosgene is 1:(0.66-0.70); 2, pumping 60-90% of the 1,4-butanediol weighed in step 1 into the reaction kettle, heating the 1,4-butanediol to 40-70 DEG C, adding the triphosgene, and performing stirring until complete dissolving is achieved; 3, pumping the 1,4-butanediol remained the after step 1 and the catalyst into the elevated tank ofthe reaction kettle, performing dissolving until clarity in the reaction kettle, slowly dropwise adding a solution obtained in the elevated tank into the reaction kettle, and collecting a gas generated by a reaction; and 4, lowering the temperature to 0-30 DEG C after the reaction is finished, standing for layering, and collecting the obtained lower yellowish oily liquid to complete the preparation of 1,4-dichlorobutane. The 1,4-dichlorobutane production technology has the advantages of simplicity in operation, mild reaction conditions, greenness, no pollution, low carbon, environmental protection, and realization of large-scale production.
