634-66-2

Basic information

• Product Name: 1,2,3,4-Tetrachlorobenzene
• Synonyms: 1,2,3,4-tcb;1,2,3,4-tetrachloro-benzen;tetrachlorobenzene(non-specificname);1,2,3,4-TETRACHLOROBENZENE;Tetrachlorobenzene;1,2,3,4-TETRACHLOROBENZENE, 500MG, NEAT;1,2,3,4-TETRACHLOROBENZENE, 1X1ML MEOH 2 000UG/ML;1,2,3,4-TETRACHLOROBENZENE, TECH., 90%
• CAS NO: 634-66-2
• Molecular Formula: C₆H₂Cl₄
• Molecular Weight: 215.89
• EINECS: 211-214-0
• Product Categories: Organics;Pesticides&Metabolites;Q-ZAlphabetic;Alpha Sort;TA - TE;T-ZAlphabetic;Volatiles/ Semivolatiles;Aryl;C6;Halogenated Hydrocarbons;Canada;International Standards;Single Component Standards for MISA AnalysesVolatiles/ Semivolatiles
• Mol File: 634-66-2.mol

Chemical Properties

• Melting Point: 44 °C
• Boiling Point: 254 °C761 mm Hg(lit.)
• Flash Point: >230 °F
• Appearance: /
• Density: 1,73 g/cm3
• Vapor Pressure: 0.0363mmHg at 25°C
• Refractive Index: 1.5348 (estimate)
• Storage Temp.: APPROX 4°C
• Solubility: 0.0028g/l
• Water Solubility: 5.92mg/L(25 oC)
• BRN: 1910025
• CAS DataBase Reference: 1,2,3,4-Tetrachlorobenzene(CAS DataBase Reference)
• NIST Chemistry Reference: 1,2,3,4-Tetrachlorobenzene(634-66-2)
• EPA Substance Registry System: 1,2,3,4-Tetrachlorobenzene(634-66-2)

Safety Data

• Hazard Codes: Xn,T,F
• Statements: 22-39/23/24/25-23/24/25-11
• Safety Statements: 22-24/25-45-16-7-36/37
• RIDADR: 3077
• WGK Germany: 3
• RTECS: DB9440000
• Hazardous Substances Data: 634-66-2(Hazardous Substances Data)

Usage

Uses

Used in Dielectric Fluids:
1,2,3,4-Tetrachlorobenzene is used as a component in dielectric fluids for its high resistance to electrical conductivity and thermal stability. Dielectric fluids are essential in various industrial applications, such as transformers and capacitors, to provide insulation and cooling.
Used in Synthesis:
1,2,3,4-Tetrachlorobenzene serves as a key intermediate in the synthesis of various organic compounds, including pharmaceuticals, agrochemicals, and dyes. Its unique chemical structure allows for the formation of a wide range of products through chemical reactions.
Used in Environmental Analysis:
1,2,3,4-Tetrachlorobenzene is used as a model compound to determine the presence and concentration of chlorobenzenes (CBs) in soil samples. This helps in assessing the level of environmental contamination and taking necessary remedial measures.
Used in Rapid Dechlorination:
1,2,3,4-Tetrachlorobenzene is utilized for the rapid dechlorination of 1,2,3,4-tetrachlorodibenzo-p-dioxin (1,2,3,4-TeCDD), a highly toxic and persistent environmental pollutant. The dechlorination process helps in reducing the environmental impact and potential health risks associated with 1,2,3,4-TeCDD exposure.

Air & Water Reactions

Insoluble in water.

Reactivity Profile

Simple aromatic halogenated organic compounds, such as 1,2,3,4-Tetrachlorobenzene, are very unreactive. Reactivity generally decreases with increased degree of substitution of halogen for hydrogen atoms. Materials in this group may be incompatible with strong oxidizing and reducing agents. Also, they may be incompatible with many amines, nitrides, azo/diazo compounds, alkali metals, and epoxides.

Health Hazard

ACUTE/CHRONIC HAZARDS: 1,2,3,4-Tetrachlorobenzene may cause irritation of the skin.

Fire Hazard

1,2,3,4-Tetrachlorobenzene is probably combustible.

Safety Profile

Moderately toxic by ingestion. An experimental teratogen. Experimental reproductive effects. Irritant. Combustible liquid. When heated to decomposition it emits toxic fumes of Cl-. See also CHLORINATED HYDROCARBONS, AROMATIC.

Environmental fate

Biological. A mixed culture of soil bacteria or a Pseudomonas sp. transformed 1,2,3,4- tetrachlorobenzene to 2,3,4,5-tetrachlorophenol (Ballschiter and Scholz, 1980). After incubation in sewage sludge for 32 d under anaerobic conditions, 1,2,3,4-tetrachlorobenzene did not biodegrade (Kirk et al., 1989). The half-life of 1,2,3,4-tetrachlorobenzene in an anaerobic enrichment culture was 26.4 h (Beurskens et al., 1993). Potrawfke et al. (1998) reported that a pure culture of Pseudomonas chlororaphis RW71 mineralized 1,2,3,4-tetrachlorobenzene as a sole source of carbon and energy. Intermediate biodegradation products identified were tetrachlorocatechol, tetrachloromuconic acid, 2,3,5-trichlorodienelactone, 2,3,5-trichloro-4-hydroxymuconic acid. In an enrichment culture derived from a contaminated site in Bayou d’Inde, LA, 1,2,4,5- tetrachlorobenzene underwent reductive dechlorination yielding 1,2,4-trichlorobenzene. The maximum dechlorination rate, based on the recommended Michaelis-Menten model, was 208 nM/d (Pavlostathis and Prytula, 2000). Photolytic. Irradiation (λ ≥285 nm) of 1,2,3,4-tetrachlorobenzene (1.1–1.2 mM/L) in an acetonitrile-water mixture containing acetone (0.553 mM/L) as a sensitizer gave the following products (% yield): 1,2,3-trichlorobenzene (9.2), 1,2,4-trichlorobenzene (32.6), 1,3-dichlorobenzene (5.2), 1,4-dichlorobenzene (1.5), 2,2′,3,3′,4,4′,5-heptachlorobiphenyl (2.52), 2,2′,3,3′,4,5,6′- heptachlorobiphenyl (1.22), 10 hexachlorobiphenyls (3.50), five pentachlorobiphenyls (0.87), dichlorophenyl cyanide, two trichloroacetophenones, trichlorocyanophenol, (trichlorophenyl) acetonitriles, and 1-(trichlorophenyl)-2-propanone (Choudhry and Hutzinger, 1984). Without acetone, the identified photolysis products (% yield) included 1,2,3-trichlorobenzene (7.8), 1,2,4- trichlorobenzene (26.8), 1,2-dichlorobenzene (0.5), 1,3-dichlorobenzene (0.7), 1,4-dichloro-benzene (30.4), 1,2,3,5-tetrachlorobenzene (2.26), 1,2,4,5-tetrachlorobenzene (0.72), 2,2′,3,3′,4,4′,5- heptachlorobiphenyl (<0.01), and 2,2′,3,3′,4,5,6′-heptachlorobiphenyl (<0.01) (Choudhry and Hutzinger, 1984). The sunlight irradiation of 1,2,3,4-tetrachlorobenzene (20 g) in a 100-mL borosilicate glass-stoppered Erlenmeyer flask for 56 d yielded 4,280 ppm heptachlorobiphenyl (Uyeta et al., 1976).

Solubility in water

Soluble in acetic acid, ether, ligroin (Weast, 1986), and very soluble in many chlorinated solvents including chloroform, carbon tetrachloride, etc.

Purification Methods

Crystallise it from EtOH. [Beilstein 5 H 204, 5 II 156, 5 III 550, 5 IV 667.]

InChI:InChI=1/C6H2Cl4/c7-3-1-4(8)6(10)5(9)2-3/h1-2H

Upstream product

• 634-67-3 2,3,4-trichloroaniline 
• 1890-41-1 optically inactive 1,2,3,4,5,6-hexachloro-cyclohexene 
• 117-08-8 tetrachlorophthalic anhydride 
• 15944-74-8 3,6-dichloro-2-nitro-aniline 
• 57722-16-4 (36/45)-hexachlorocyclohexene 
• 120-82-1 1,2,4-Trichlorobenzene 
• 87-61-6 1,2,3-trichlorobenzene 
• 35608-94-7 1,2,3,4-tetrachloro-1,3-cyclohexadiene 
• 95-94-3 1,2,4,5-tetrachlorobenzene 
• 608-93-5 pentachlorobenzene 
• 38411-21-1 2,3,4,5-tetrachloroiodobenzene 
• 68-12-2 N,N-dimethyl-formamide 
• 121-46-0 bicyclo[2.2.1]hepta-2,5-diene 
• 90454-50-5 N-ethoxycarbonyl-(2,3,4,5-tetrachloro-1-thiophenio)amide 

Downstream Products

• 933-75-5 2,3,6-trichlorophenol 
• 54135-80-7 1,2,3-trichloro-4-methoxybenzene 
• 879-39-0 2,3,4,5-tetrachloronitrobenzene 
• 13074-97-0 1,2-dibromo-3,4,5,6-tetrachloro-benzene 
• 51527-63-0 2,3,4,5-tetrachlorobenzenesulfonyl chloride 
• 40707-33-3 o-HC₆Cl₄SO₃H 
• 876498-70-3 4H-nonachloro-cyclohexene 
• 859180-73-7 4H,5H-octachloro-cyclohexene 
• 120-82-1 1,2,4-Trichlorobenzene 
• 20082-68-2 1,2,4-Trichlor-5-trimethylsilylbenzol 
• 20450-35-5 1,2,3,4-Tetrachlor-5-trimethylsilylbenzol 
• 55215-18-4 2,2',3,3',4,5-hexachlorobiphenyl 
• 60145-23-5 2,2',3,4,4',5',6-heptachlorobiphenyl 
• 97985-54-1 2,3,4,5-tetrachloro-1-(trifluoromethyl)benzene 

Relevant articles and documents

Photoisomerisation of bicyclo[4.2.0]octadienes to tricyclo[4.2.0.02,5] octenes: Application to the synthesis of [n]ladderanes

A new approach for the extension of [n]ladderanes is described which involves formation of an end-fused bicyclo[4.2.0]octadiene and its photoisomerisation to the related tricyclo[4.2.0.02,5] octene as the ladderane extension step. The protocol is illustrated with the synthesis of [3]ladderane (9) from an unsubstituted cyclobutene and nor[5]ladderane (13) from an ester activated cyclobutene. The exo-stereochemistry of (13) is confirmed by reference to intermediate (23) for which a single crystal X-Ray structure analysis was obtained.

Photochemistry of Polyhaloarenes. 7. Photodechlorination of Pentachlorobenzene in the Presence of Sodium Borohydride

The mechanism of photodechlorination of pentachlorobenzene (1) in acetonitrile has been examined.The quantum yield of reaction (Φr) has been found to vary with the concentration of 1.A charge-transfer intermediate formed from the triplet excited state of 1 is proposed to explain the observations. Φr increases with added NaBH4 and 1/Φr varies directly with the inverse of the concentration of the electron-transfer reagent.The regiochemistry deuterium isotope effects, tracer studies, and quenching analyses are consistent with an electron-transfer process.

Preparation method for 3,5,-dichloro-2,4,-difluoroaniline

The invention relates to the field of organic synthesis, specifically to a preparation method for 3,5,-dichloro-2,4,-difluoroaniline and application thereof. The preparation method for 3,5,-dichloro-2,4,-difluoroaniline provided by the invention comprises the following steps: 1) nitration reaction; 2) reduction reaction; 3) diazotization reaction; 4) nitration reaction; 5) fluorination reaction; and 6) reduction reaction. The preparation method for 3,5,-dichloro-2,4,-difluoroaniline provided by the invention has the following beneficial effects: 1) the method has mild reaction conditions, is stable and controllable, has less active sites, is insusceptible to side reaction, and has good yield and quality in the whole line; and 2) raw materials are cheap and easily available, so cost can be effectively reduced, and energy is saved; meanwhile, the use of chlorine gas is avoided, so the method is environment-friendly.

Formation and destruction of chlorinated pollutants during sewage sludge incineration

The limitations facing land filling and recycling and the planned ban on sea disposal of sludge leads to the expectation that the role of sludge incineration will increase in the future. The expected increase in sludge incineration will also increase scrutiny of the main drawback to sewage sludge incineration-the formation of hazardous air pollutants (HAPs). Despite the extensive body of knowledge available on sewage sludge combustion, very few studies have been conducted on the formation of HAPs during sludge combustion. In this work, the interactions between sewage sludge pyrolysis products and sludge ash were investigated using a dual chamber flow reactor system and a horizontal laboratory scale reactor. The results of this study shows that sludge ash can catalyze oxidation and chlorination of organics. In the absence of HCl in the gas stream, sludge ash acts as an oxidizing catalyst, but in the presence of HCl, sludge ash acts as a chlorination catalyst producing high yields of organochloride compounds.

Radiation induced catalytic dechlorination of hexachlorobenzene on oxide surfaces

Radiation induced catalytic dehalogenation of hexachlorobenzene (HCB) adsorbed to alumina (Al2O3), silica (SiO2), titania (TiO2), zirconia (ZrO2), and a commercially available zeolite has been studied using Cobalt-60 (60Co) as a radiation source. Solid-particulate samples were irradiated over a dose range of 0-58 kGy, and the chemical changes were monitored using Fourier transform infrared diffuse reflectance (FTIR-DR) and gas chromatography with electron capture detection (GC-ECD). The extent of HCB degradation on the metal oxides was found to increase dramatically in samples evacuated under vacuum, pointing to the competitive scavenging of conduction band electrons by surface adsorbed species, primarily oxygen. Coadsorbed water diminished HCB conversion on all oxides but to a greater degree on alumina. HCB degradation on metal oxides was found to be highly dependent upon the conduction band energy of the support material, thus confirming the occurrence of ultra-band-gap excitation and charge separation in irradiated oxides. Higher yields of dechlorination products were witnessed in alumina and silica samples. Zeolite, titania, and zirconia were also found to be inefficient in promoting radiation induced catalysis. The absence of oxidation products in the irradiated HCB/oxide samples suggests the inaccessibility of holes to undergo interfacial charge transfer with the organic substrate.

Reactions of 2,4,6-trichlorophenol on model fly ash: Oxidation to CO and CO2, condensation to PCDD/F and conversion into related compounds

Thermal treatment of 2,4,6-trichlorophenol on a magnesium silicate-based model fly ash in the temperature range between 250°C and 400°C leads predominantly to carbon monoxide and carbon dioxide. The fraction of 2,4,6-trichlorophenol which is oxidized to CO and CO2 increases from 3% at 250°C to 75% at 400°C. Further products are polychlorinated benzenes, dibenzo-p-dioxins, dibenzofurans and phenols. The homologue and isomer patterns of the chlorobenzenes suggest chlorination in the ipso-position of the trichlorophenol. The formation of PCDD from 2,4,6-trichlorophenol and 2,3,4,6-tetrachlorophenol on municipal solid waste incinerator fly ashes and model fly ash were compared and the reaction order calculated.

Identification of surrogate compounds for the emission of PCDD/F (I-TEQ value) and evaluation of their on-line realtime detectability in flue gases of waste incineration plants by REMPI-TOFMS mass spectrometry

Correlations between products of incomplete combustion (PIC), e.g., chloroaromatic compounds, can be used to characterise the emissions from combustion processes, like municipal or hazardous waste incineration. A possible application of such relationships may be the on-line real-time monitoring of a characteristic surrogate, e.g., with Resonance-Enhanced Multiphoton Ionization-Time-of-Flight Mass Spectrometry (REMPI-TOFMS). In this paper, we report the relationships of homologues and individual congeners of chlorinated benzenes (PCBz), dibenzo-p-dioxins (PCDD), dibenzofurans (PCDF) and phenols (PCPh) to the International Toxicity Equivalent (I-TEQ) of the PCDD/F (I-TEQ value) in the flue gas and stack gas of a 22 MW hazardous waste incinerator (HWI). As the REMPI detection sensitivity is decreasing with the increase of the degree of chlorination, this study focuses on the lower chlorinated species of the compounds mentioned above. Lower chlorinated species, e.g., chlorobenzene (MCBz), 1,4-dichlorobenzene, 2,4,6-trichlorodibenzofuran or 2,4-dichlorophenol, were identified as I-TEQ surrogates in the flue gas. In contrast to the higher chlorinated phenols, the lower chlorinated phenols (degree of chlorination 4) were not reliable as surrogates in the stack gas. The identified surrogates are evaluated in terms of their detectability by REMPI-TOFMS laser mass spectrometry. The outcome is that MCBz is the best suited surrogate for (indirect) on-line measuring of the I-TEQ value in the flue gas by REMPI-TOFMS. The correlation coefficient r of the MCBz concentration to the I-TEQ in the flue gas was 0.85.

Radiolytic reduction of hexachlorobenzene in surfactant solutions: A steady-state and pulse radiolysis study

Steady-state and pulse radiolysis experiments have been performed to gain insight into the mechanism of hexachlorobenzene (HCB) degradation in nonionic surfactant (Plurafac RA-40) solutions. This understanding is important for the environmental application of radiolysis to remediate soils contaminated with chlorinated aromatic compounds or to treat surfactant solution wastes from soil washing processes. Steady-state experiments showed that, after an applied dose of 50 kGy, reductive dechlorination of HCB to trichlorobenzene occurs under reducing conditions. Under oxidizing conditions at the same dose, reductive dechlorination proceeds more slowly to yield tetrachlorobenzene. Radiolytic experiments on the surfactant alone showed that the reaction rate constant between hydroxyl radicals and RA-40 (1.09 x 109 M-1 s-1) was nearly 2 orders of magnitude higher than that between hydrated electrons and RA-40 (2.0 x 107 M-1 s-1). Reaction kinetics analysis indicates efficient hydroxyl radical scavenging by surfactant molecules and the production of secondary surfactant radicals, which are reductive in nature. Thus, we observe HCB dechlorination in surfactant solutions even under strongly oxidizing conditions. Steady-state and pulse radiolysis experiments have been performed to gain insight into the mechanism of hexachlorobenzene (HCB) degradation in nonionic surfactant (Plurafac RA-40) solutions. This understanding is important for the environmental application of radiolysis to remediate soils contaminated with chlorinated aromatic compounds or to treat surfactant solution wastes from soil washing processes. Steady-state experiments showed that, after an applied dose of 50 kGy, reductive dechlorination of HCB to trichlorobenzene occurs under reducing conditions. Under oxidizing conditions at the same dose, reductive dechlorination proceeds more slowly to yield tetrachlorobenzene. Radiolytic experiments on the surfactant alone showed that the reaction rate constant between hydroxyl radicals and RA-40 (1.09 × 109 M-1 s-1) was nearly 2 orders of magnitude higher than that between hydrated electrons and RA-40 (2.0 × 107 M-1 s-1). Reaction kinetics analysis indicates efficient hydroxyl radical scavenging by surfactant molecules and the production of secondary surfactant radicals, which are reductive in nature. Thus, we observe HCB dechlorination in surfactant solutions even under strongly oxidizing conditions.

Pyrolysis of tricyclic cyclobutane-fused sulfolanes as a route to cis-1,2-divinyl compounds and their Cope-derived products

Functionalisation of the double bond of 3-thiabicyclohept-6-ene 3, readily formed by hydrolysis of the cycloadduct 1 of 3-sulfolene and maleic anhydride followed by oxidative bis-decarboxylation, gives tricyclic sulfones 5-7 and 9 with the bicyclo2,4> skeleton. FVP of 3 results in stereospecific extrusion of SO2 to give Z-hexa-1,3,5-triene which undergoes electrocylisation to give cyclohexa-1,3-diene while reaction of 3 with LiAlH4 results in non-stereospecific extrusion to give Z- and E-hexa-1,3,5-triene. Upon FVP the tricyclic sulfones 5-7 and 9 lose SO2 to give 7-membered ring products 16-19 by Cope rearrangement of the initially formed cis-1,2-divinyl intermediates 15. The 1,3-dipolar cycloaddition of nitrile oxides and a nitrone to the double bond of 3 gives tricyclic sulfones with the tricyclo2,6> skeleton and a wider variety of these can be prepared by conventional reactions of 1. Upon FVP these lose SO2 to give stable cis-1,2-divinyl compounds 23, 24, 37-40 and 41-44. The Diels-Alder adducts 48 and 49 have been prepared from 3 and these behave differently upon FVP, losing SO2 and butadiene to give tetrasubstituted benzenes, in the latter case by way of an unexpected tetracyclic intermediate.

Catalytic Dehalogenation of Highly Chlorinated Benzenes and Aroclors Using PdCl2(dppf) and NaBH4: Efficiency, Selectivity, and Base Support

Reported herein is a convenient one-pot system that can dehalogenate highly chlorinated benzenes at room temperature with reasonable conversion rates using PdCl2(dppf) (dppf = 1,1′-bis-(diphenylphosphino)ferrocene) as catalyst, NaBH4 as reducing agent, TMEDA (N,N,N',N'-tetra-methyl-1,2-ethylenediamine) as supporting base, and THF as solvent. Total conversion of substrate to less chlorinated isomers is achieved within 200 h when hexachloro-, pentachloro-, and tetrachlorobenzenes are used. Degradation to benzene is not achievable, but the efficiency shown in the partial dechlorination is encouraging. A pronounced selectivity is accomplished with removal of meta-substituted chlorines being preferred over ortho- or para-substituted Cl atoms. The sequence in which reagents are added is also critical, thus indicating a protective role of the base. The effectiveness of the method was tested on the PCB mixtures Aroclor 1242, 1248, and 1254. Dechlorination efficiency at 67 °C is satisfactory.