876-86-8

The invention provides a preparation method of hexachloro-1,3-butadiene. The preparation method has the characteristics as follows: trichlorethylene and tetrachlorethylene are used as raw materials, anhydrous metal chloride is used as a catalyst, the metal chloride can be one or more of ferric chloride, aluminum chloride and zinc chloride, a reactant is one or two of trichlorethylene and tetrachlorethylene, the molar ratio of the trichloroethylene to the tetrachlorethylene is 0:100 to 100:0, and the mass fraction of the catalyst is 1-20%. Under the condition that the reaction temperature is 50-250 DEGC, the conversion rate of the reactant is 20-80%, and the selectivity of the hexachloro-1,3-butadiene is 20-60%. The preparation method is simple in process, simple and convenient in operation, low in energy consumption and high in atom utilization rate.

The kinetics and mechanism of an addition of CCl4 to oct-1-ene initiated by amines, aromatic alcohols, and amino alcohols (structural analogs of ephedrin) were studied. The radical mechanism of the reaction was established by ESR using the technique of spin traps. Aromatic amino alcohols as initiators are more active than amines and aromatic alcohols of similar structure. They are more selective compared to the amines and aromatic alcohols and react with CCl4 already at room temperature to form predominantly benzaldehyde. The scheme of initiation by aromatic amino alcohols of the addition of CCl 4 to olefins was proposed on the basis of the experimental data.

Previous workers have investigated the reaction of tetrachloroethene using thermal initiation and CO2-laser initiation via sensitizing species. In both instances, the principal product was found to be hexachlorobenzene. One group reported evidence of laser specificity in this reaction, in that BCl3 acted as a sensitizer to produce hexachlorobenzene as the principal product, but SF6 and BBr3 did not. We have found that specificity is highly dependent on reaction conditions. We reproduced the previous results using similar experimental conditions, but under different conditions, we found that the specificity is lost, with all three sensitizers which we used (BCl3, SF6, and SiF4) sensitizing the reaction to produce mainly hexachlorobenzene. There were some differences among the sensitizers, as, for example, the fact that SF6 produced the most nearly pure hexachlorobenzene product.

The formation of organochlorines during the electrolytic production of magnesium was investigated using a laboratory-scale electrolytic cell having a graphite anode, a liquid aluminium alloy cathode, and a molten chloride electrolyte. The cell was operated at current densities ranging from 3000 to 10,000 A m-2 and at temperatures ranging from 660°C to 750°C. Organochlorines were adsorbed from the cell off-gases onto silica gel, extracted with hexane, and determined by gas chromatography. All compounds identified were fully chlorinated aliphatic and aromatic compounds, the major components being hexachlorobutadiene, hexachlorobenzene, hexachloroethylene, and octachlorostyrene. The total amount of organochlorines per tonne of magnesium produced decreased with electrolysis time and with current density and increased with operating temperature; it was also dependent on the type of graphite employed. The output of organochlorines Varied from 5 to 20 g t-1 of magnesium.

The chlorination and condensation of acetylene at low temperatures is demonstrated using copper chlorides as chlorinated agents coated to model borosilicate surfaces. Experiments with and without both a chlorine source and borosilicate surfaces indicate the absence of gas-phase and gas-surface reactions. Chlorination and condensation occur only in the presence of the copper catalyst. C2 through C8 organic products were observed in the effluent; PCDD/F were only observed from extraction of the borosilicate surfaces. A global reaction model is proposed that is consistent with the observed product distributions. Similar experiments with dichloroacetylene indicate greater reactivity in the absence of the copper catalyst. Reaction is observed in the gas-phase and in the presence of borosilicate surfaces at low temperatures. The formation of hexachlorobenzene is only observed in the presence of a copper catalyst. PCDD/F were only observed from extraction of the borosilicate surfaces. A global reaction model is proposed for the formation of hexachlorobenzene from dichloroacetylene. (C) 2000 Elsevier Science Ltd.

1-Bromo-1,2,4,4-tetrachloro-1,3-butadiene reacts with chlorosulfonic acid to give 1,3-dibromo1,2,4,4-tetrachloro-1,3-butadiene, bromochloromaleic acid, and hexachlorobutadiene. 1,3-Dibromo-1,2,4,4-tetrachloro-1,3-butadiene was also obtained by bromination of 1-bromo-1,2,4,4-tetrachloro-l,3-butadiene and subsequent dehydrobromination; 1,2,4-tribromo-1,3,4-trichloro-1,3-butadiene was also formed as by-product.

We examined the thermally induced acetylene chlorination and condensation reactions on different types of copper salt impregnated surfaces. The System for Thermal Diagnostic Studies provided a powerful tool to study these reactions under defined reaction conditions, which were related to typical conditions in postcombustion incineration processes. Experiments were conducted with acetylene or acetylene/HCl mixtures in a quarts reactor filled with a borosilicate foam of known pore size at temperatures between 150 and 500 °C. Borosilicate was also used as the catalytic support for gas-solid reactions of acetylene and acetylene/HCl mixtures with CuCl2 and CuO. Reaction products were trapped in-line and analyzed by GC/MS. It was shown that borosilicate is not able to catalyze acetylene condensation reactions. CuCl2-impregnated borosilicate was a highly effective catalyst for acetylene chlorination/condensation reactions at temperatures above 150 °C. The same behavior was found for CuO- impregnated borosilicate in the presence of HCl. However, temperatures above 300 °C were required for this catalytic system. Mainly perchlorinated C-2 to C-8 hydrocarbons were trapped as reaction products in the gas phase. Maximum yields for acetylene chlorination/condensation reactions in each related catalytic system were found at temperatures between 300 and 400 °C. Results of the surface-catalyzed acetylene chlorination and condensation reactions were summarized in a global mechanism. A ligand transfer oxidative chlorination of acetylene with CuCl2 was proposed to be the initiation of acetylene with CuCl2 was proposed to be the initiating step. Chlorinated acetylene then condenses to higher molecular weight compounds, catalyzed by CuCl in metallacyclization reactions. We examined the thermally induced acetylene chlorination and condensation reactions on different types of copper salt impregnated surfaces. The System for Thermal Diagnostic Studies provided a powerful tool to study these reactions under defined reaction conditions, which were related to typical conditions in postcombustion incineration processes. Experiments were conducted with acetylene or acetylene/HCl mixtures in a quartz reactor filled with a borosilicate foam of known pore size at temperatures between 150 and 500 °C. Borosilicate was also used as the catalytic support for gas-solid reactions of acetylene and acetylene/HCl mixtures with CuCl2 and CuO. Reaction products were trapped in-line and analyzed by GC/MS. It was shown that borosilicate is not able to catalyze acetylene condensation reactions. CuCl2-impregnated borosilicate was a highly effective catalyst for acetylene chlorination/condensation reactions at temperatures above 150 °C. The same behavior was found for CuO-impregnated borosilicate in the presence of HCl. However, temperatures above 300 °C were required for this catalytic system. Mainly perchlorinated C-2 to C-8 hydrocarbons were trapped as reaction products in the gas phase. Maximum yields for acetylene chlorination/condensation reactions in each related catalytic system were found at temperatures between 300 and 400 °C. Results of the surface-catalyzed acetylene chlorination and condensation reactions were summarized in a global mechanism. A ligand transfer oxidative chlorination of acetylene with CuCl2 was proposed to be the initiating step. Chlorinated acetylene then condenses to higher molecular weight compounds, catalyzed by CuCl in metallacyclization reactions.

Pyridine hydrochloride has been widely used in the cleavage of ethers. It is shown herein that his reagent is also efficient for the synthesis of chloro compounds starting from the corresponding bromo derivatives in π-deficient series such as pyridine and quinoline. Thus, for example, 7-bromo-8-hydroxyquinoline was almost quantitatively converted into 7-chloro-8-hydroxyquinoline. The scope of the reaction has been studied.

Previous report on the thermal or CO2-laser induced decomposition of trichloroethylene have identified only one condensable product, hexachlorobenzene (in addition to HCl and mono- and dichloroacetylene).We have found that trichloroethylene vapor exposed to cw irradiation on the P(24) line of the (001-100) band of the CO2 laser at incident power levels from 8-17 W procedures numerous products, of which the 13 major ones have been identified using IR, GC/MS, GC/FTIR, and NMR methods.All of these products have 4, 6, or 8 carbons, are highly unsaturated, and are completely chlorinated or contain a single hydrogen.C4HCl5 and C6Cl6 isomers (three of each) account for ca. 55percent to 85percent of total products (based on peak area in the total ion chromatograms in GC/MS runs), depending on reaction conditions.In addition to characterizing the products, we discuss the dependence of the product distribution on laser power, irradiation time, and cell geometry, and we outline a possible mechanism.

1,1,1,2,4,4,4-Heptafluoro-2-butene and 2-chloro-1,1,1,4,4,4,-hexafluoro-2-butene are prepared simultaneously by reacting hexachlorobutadiene with hydrogen fluoride with the addition of catalytic amounts of titanium halide, antimony trihalide and/or antoimony pentahalide.

The previously unknown 1-nitropentachloro-1-butadiene was obtained by the action of 57-68percent nitric acid on cis-1-H-pentachloro-1,3-butadiene at 70-75 deg C.The reaction of nitrodiene with sodium alcoholates takes place with substitution of the nitro group and leads to a 3:1 mixture of the cis and trans isomers of the respective 1-alkoxy-1,2,3,4,4-pentachloro-1,3-butadienes.The action of primary and secondary amines and also of monoethanolamine on the nitrodiene leads to substitution of the chlorine atom at the second carbon atom of the diene system and the formationof 1-nitro-2-amino-1,3,4,4-tetrachloro-1,3-butadienes.The reaction of the nitrodiene with ethylenediamine takes place with substitution of the chlorine atoms in two molecules of the nitrodiene and leads to N,N'-bis(1-nitro-1,3,4,4-tetrachloro-1,3-butadienyl)ethylenediamine.It was established that the amino derivatives of the nitrodiene are formed as a single isomer

2,3,3,4,4-Pentachlorobutyric acid was obtained with a preparative yield by the reaction of 1,1,1,2,3,3,4,4-octachlorobutane with oleum.The dehydrochlorination of octachlorobutane with an equimolar amount of an aqueous solution of sodium hydroxide, catalyzed by triethylbenzylammonium chloride, takes place by the elimination of one molecule of hydrogen chloride from positions 1,2 and 2,3 with the formation of isomeric heptachlorobutenes.Hydrolysis of the latter with fuming nitric acid gave the difficultly obtainable 1,1,2,4,4-pentachloro-1-buten-3-one and Z-α,β,χ,χ-tetrachlorocrotonic acid.

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1,1,1-Trichloro- and tribromo polyfluoroalkanes have been synthesized from perfluoroalkyl iodides and anhydrous aluminium chloride and bromide respectively.The reaction is also applicable to perfluoroalkylether iodides, though varying amounts of by-products are formed depending on the structure of the starting iodode.

The chlorination of 2-H-pentachloro-1,3-butadiene with gaseous chlorine in the presence of antimony pentachloride at 10-15 deg C was investigated.It was shown that the chlorine adds at positions 1,2 and 3,4 with the formation of a mixture of 1,1,1,2,3,4,4-heptachloro-3-butene and 1,1,3,3,4,4,4-heptachloro-1-butene in a ratio of 72.8:27.2 respectively.The action of 100percent nitric acid on 1,1,3,3,4,4,4-heptachloro-1-butene gave β,γ,γ,γ-tetrachlorocrotonic acid.

Phenol as well as 3-substituted phenols are brominated exclusively in the ortho positions by N.N-dibromomethylamine, yielding 2.6-dibrominated phenols in excellent yields.Phenols bearing an ortho-substituent need N-bromomethylamine as the brominating agent to take up one bromine atom into the free ortho-position. para-Bromination is not observed in either case. 1-Naphthol gives 2-bromo-1-naphthol, 8-hydroxyquinoline gives 7-bromo-8-hydroxyquinoline with 80percent and 98percent yield respectively. ortho-Specific chlorination of phenols was carried out in some cases using N-chloro-alkylamines.

The free-radical reaction of diaryl disulfides ArSSAr with CHCl=CCl2 leads to aryl β,β- and α,β-dichlorovinyl sulfides, trichlorovinyl sulfides, and the trichloroethylene dimer 1,1,3,3,4,4,-hexachloro-1-butene.In the reaction of diaryl disulfides with tetrachloroethylene aryl trichlorovinyl sulfides and hexachloro-1,3-butadiene are formed.A reaction mechanism involving reaction of the vinyl radicals CCl2=C.Cl, CCl2=C.H, adn CHCl-C.Cl with the arylthiyl radical is proposed.

The direct chlorosulfonylation of polychlorodiene systems was realized for the first time for the case of the reaction of 2-H-pentachloro-1,3-butadiene with chlorosulfonic acid.A series of 1-alkyl(aryl)amino-1,3,4,4-tetrachloro-2--1,3-butadienes were synthesized by the reaction of the obtained 1,1,3,4,4-pentachloro-1,3-butadiene-2-sulfonyl chloride with amines.

During the condensation of 2-H-pentachloro-1,3-butadiene with carbon tetrachloride in the presence of anhydrous aluminum chloride 2-trichloromethyl-1,1,3,4,4-pentachloro-1,3-butadiene, octachlorocyclopentene, and 1,2,3,3,5,5-hexachloro-4-(dichloromethylene)cyclopentene are formed as the main products.A possible mechanism for their formation is proposed.It was established that the C2 atom in th 2-H-pentachloro-1,3-butadiene molecule is the most favorable for attack by the trichloromethyl cation.

Pyrolysis of octachlorotetrahydrothiophene 1,1-dioxide provides a practical synthesis of octachlorocyclobutane. 1,2-Dichlorohexafluorotetrahydrothiophene 1,1-dioxide also yields a cyclobutane.Treatment of these sulfones with potassium hydroxide forms perhalogenated 3-butenesulfonates.From octachloro-2,3-dihydrobenzothiophene 1,1-dioxide, octachlorostyrene is produced by pyrolysis and hexachlorobenzothiophene 1,1-dioxide by treatment with sodium iodide.Hexachlorobenzothiophene has been prepared from octachloro-2,3-dihydrobenzothiophene and oxidized with chromium trioxide to a thiolactone (17).Hydrolysis of the latter gives a 2H-benzothiete (18).Oxidation of tetrachlorothiophene forms the thiolactone tetrachloro-2,3-dihydrothiophen-2-one (19).Octachlorodibenzothiophene can be made by direct chlorination.

The reaction of tetrachloroethylene with hydrogen sulfide at 450-500 deg C leads to the formation of tetrachlorothiophene as the principal product, along with hexachlorobutadiene, the yield of which increases as the reaction temperature is raised.