1190-22-3Relevant academic research and scientific papers
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.
A mild method for the replacement of a hydroxyl group by halogen. 1. Scope and chemoselectivity
Munyemana, Fran?ois,George, Isabelle,Devos, Alain,Colens, Alain,Badarau, Eduard,Frisque-Hesbain, Anne-Marie,Loudet, Aurore,Differding, Edmond,Damien, Jean-Marie,Rémion, Jeanine,Van Uytbergen, Jacqueline,Ghosez, Léon
, p. 420 - 430 (2015/12/31)
α-Chloro-, bromo- and iodoenamines, which are readily prepared from the corresponding isobutyramides have been found to be excellent reagents for the transformation of a wide variety of alcohols or carboxylic acids into the corresponding halides. Yields are high and conditions are very mild thus allowing for the presence of sensitive functional groups. The reagents can be easily tuned allowing therefore the selective monohalogenation of polyhydroxylated molecules. The scope and chemoselectivity of the reactions have been studied and reaction mechanisms have been proposed.
Absolute rate constants for abstraction of chlorine from three chlorinating agents by alkyl radicals
Tanko, James M.,Blackert, Joseph F.
, p. 1775 - 1780 (2007/10/03)
Using the cyclopropylcarbinyl -> homoallyl free radical clock, absolute rate constants for the abstraction of chlorine from molecular chlorine (Cl2), tert-butyl hypochlorite (ButOCl) and N-chloro-3,3-dimethylglutarimide (NCG) have been determined (kCl2=3.0*1010, kButOCl=2.6*109 and kNCG=3.6*107, all in 1 mol-1s-1).
HYDROCHLORINATION OF UNSATURATED COMPOUNDS BY THE ACTION OF CH2Cl2 OR CHCl3 AND RHODIUM COMPLEXES
Khusnutdinov, R. I.,Shchadneva, N. A.,Dzhemilev, U. M.,Tolstikov, G. A.
, p. 1213 - 1217 (2007/10/02)
A new method has been developed for the catalytic hydrochlorination of olefins and acetylenes in the presence of Rh complexes by means of HCl generated in situ from CH2Cl2 and CHCl3 under the reaction conditions.The reaction was studied using the hydrochlorination of propylene, 1-hexene, 1-nonene, vinylcyclopropane, 1,1-dicyclopropylethylene, cyclohexene, cyclooctene, norbornene, and 1,5-cyclooctadiene as examples.
Versatility of Zeolites as Catalysts for Ring or Side-Chain Aromatic Chlorinations by Sulfuryl Chloride
Delaude, Lionel,Laszlo, Pierre
, p. 5260 - 5269 (2007/10/02)
Zeolites catalyze chlorination of aromatics by sulfuryl chloride SO2Cl2.It is possible by an appropriate choice of the catalyst to effect at will, with very high selectivity, either the ring or the side-chain chlorination.Zeolite ZF520 is the choice catalyst for the former, because of its high Broensted acidity.Zeolite NaX (13X) is a fine catalyst for the latter, free-radical chlorination; the reaction is best effected in the presence of a light source; the catalyst can be reused many times with no loss in activity.Both reaction modes, the ionic (ring chlorination)and the radical (side-chain substitution), are likely to occur outside of the channel network in the microporous solid.The effects of various experimental factors - such as the nature of the solvent, the reaction time and temperature, the Broensted acidity of the solid support, the presence of radical inhibitors, and the quantity of catalysts - were investigated.The procedures resulting from this study are very easy to implement in practice and are quite effective.
MECHANISMS OF FREE-RADICAL REACTIONS. XXIV. QUANTITATIVE DESCRIPTION OF THE POLAR EFFECTS OF SUBSTITUENTS ON THE KINETICS OF THE FREE-RADICAL CHLORINATION OF ALIPHATIC COMPOUNDS BY N-CHLOROPIPERIDINE
Dneprovskii, A. S.,Mil'tsov, S. A.,Arbuzov, P. V.
, p. 1826 - 1835 (2007/10/02)
The free-radical chlorination of 1-substituted alkanes with electron-withdrawing substituents by N-chloropiperidine in trifluoroacetic acid was studied by the method of competing reactions, and the relative rate constants were obtained for all positions of the substrates.The data on the position selectivity can be described satisfactorily by means of an electrostatic model of the polar effect of the substituent, calculated according to the Kirkwood-Westheimer equation.The obtained characteristics of the electrostatic effect can be successfully applied to calculation of the substrate selectivity and the intermolecular relative rate constants for all the positions, beginning with the third.The Taft equation is unsuitable for description of the effect of substituents on the reaction rate.
THE LONG-RANGE ACTION OF THE POLAR EFFECT OF SUBSTITUENTS ON THE ABSTRACTION OF HYDROGEN IN FREE-RADICAL CHLORINATION PROCESSES
Aver'yanov, V. A.,Ruban, S. G.,Klykova, M. B.,Golubev, V. E.
, p. 435 - 439 (2007/10/02)
The free-radical chlorination of 1-chloroalkanes between C3 and C6 at 263 deg K was studied under conditions with wide variation in the concentrations of the substrates in benzene.By analysis of the products from chlorination of the pure substrates it was shown that the deactivating effect of the polar substituent does not extend beyond the third carbon atom and is mainly determined by the inductive effect.In the transition to an aromatic solvent the deactivating effect on the substituent extends to the fourth carbon atom.The results are substantiated in terms of a contribution from dipole-dipole interaction between the substituent and the polar form of the transition state to the polar effect of the substituents.
MECHANISMS OF FREE-RADICAL REACTIONS. XIX. SELECTIVITY OF THE FREE-RADICAL CHLORINATION OF 1-CHLOROALKANES BY N-CHLOROPIPERIDINE
Dneprovskii, A. S.,Mil'tsov, S. A.
, p. 265 - 269 (2007/10/02)
The free-radical chlorination of 1-chloroalkanes ClH2l+1Cl (l = 4-7) by N-chloropiperidine was studied by the method of competing reactions, and the relative constants for all the positions of the investigated substrates were determined.The chlorination is a highly electrophilic process, and the effect of the substituents is transmitted through at least six C-C bonds.The results can be described satisfactorily by means of an electrostatic model of the polar effect of the substituents according to the Kirkwood-Westheimer equation.At the same time an attempt to describe the obtained data by means of the Taft equation led to unsatisfactory results.
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 (2007/10/02)
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.
