87-87-6

Usage

Uses

Used in Analytical Chemistry:
Tetrachlorohydroquinone is utilized as an analytical standard in various chemical and environmental analyses. Its properties and reactivity make it a valuable reference compound for the development and calibration of analytical methods and instruments.
Used in Environmental Research:
TCHQ's cytotoxic and reactive characteristics are relevant in environmental research, particularly in studies focused on the effects of organochlorine compounds on aquatic life and ecosystems. Understanding its impact can help in the development of strategies to mitigate the harmful effects of such pollutants.
Used in Pharmaceutical Research:
Due to its cytotoxic properties, Tetrachlorohydroquinone may be studied in pharmaceutical research for its potential applications in drug development. Its effects on cellular processes like apoptosis and ROS production could provide insights into the mechanisms of action for new therapeutic agents.
Used in Material Science:
The chemical properties of TCHQ, such as its light beige crystalline powder form, may be of interest in material science for the development of new materials with specific properties or for use in various industrial applications.

Purification Methods

Crystallise the quinone from EtOH or AcOH/EtOH. Sublime it at 77o/0.6x10-3mm. The dibenzoyl derivative has m 233o. [Conant & Fieser J Am Chem Soc 45 2207 1923, Rabideau et al. J Am Chem Soc 108 8130 1986, Beilstein 6 H 851, 6 I 417, 6 II 846, 6 III 4436, 6 IV 5775.]

InChI:InChI=1/C6H2Cl4O2/c7-1-2(8)6(12)4(10)3(9)5(1)11/h11-12H

Upstream product

• 615-93-0 2,5-Dichloro-1,4-benzoquinone 
• 7596-61-4 phosphoric acid diethyl ester-(2,3,5,6-tetrachloro-4-hydroxy-phenyl ester) 
• 697-91-6 2,6-dichloro-1,4-benzoquinone 
• 60-29-7 diethyl ether 
• 118-75-2 chloranil 
• 64-17-5 ethanol 
• 106-42-3 para-xylene 
• 634-35-5 N-ethylquinolinium iodide 
• 64-19-7 acetic acid 
• 121-44-8 triethylamine 
• 71-43-2 benzene 
• 122-51-0 orthoformic acid triethyl ester 
• 123-31-9 hydroquinone 
• 122-52-1 triethyl phosphite 

Downstream Products

• 118-75-2 chloranil 
• 7437-96-9 1,4-bis-benzoyloxy-2,3,5,6-tetrachloro-benzene 
• 36232-16-3 1,4-Bis-acetylcarbamoyloxy-2,3,5,6-tetrachlor-benzol 
• 17811-54-0 Tetrachlorohydroquinone monobenzyl ether 
• 75141-93-4 2,3,5,6-tetrachloro-1,4-bis(benzyloxy)benzene 
• 17258-75-2 Tetrachlorohydroquinone bis(trimethylsilyl) ether 
• 123395-49-3 Tetrachlorhydrochinon-1.4-bis(O-β-D-xylopyranosidtriacetat) 
• 123428-06-8 Tetrachlorhydrochinon-1.4-bis(O-β-D-glucopyranosidtetraacetat) 
• 944-78-5 1,2,4,5-tetrachloro-3,6-dimethoxybenzene 
• 25294-85-3 <2H4>Hydrochinone 
• 77787-72-5 <2H10>-1,4-cyclohexanediol 
• 109297-47-4 4-allyloxy-2,3,5,6-tetrachlorophenol 
• 172796-86-0 <α-(2,3,5,6-Tetrachlorophenoxy)benzyl>trimethylsilane 
• 172796-88-2 2,3,5,6-Tetrachloro-4-[(4-methoxy-phenyl)-trimethylsilanyl-methoxy]-phenol 

Relevant academic research and scientific papers

Synthetic Photochemistry. XXX. The Addition Reactions of Cycloheptatriene with Some Aromatic p-Quinones

The photochemical reactions of cycloheptatriene with p-benzoquinone and 1,4-naphthoquinone yielded the spirocyclic ethers, which had 7-oxabicyclonona-2,4-diene structures, by the characteristic (6+2)? cycloaddition process.The latter quinone further produced the carboxylic (2+2)? and (6+2)? cycloadducts.

Photoinduced reactions of chloranil with 1,1-diarylethenes and product photochemistry-intramolecular [2 + 2] (ortho-)cycloadditions of excited enedione's C=C double bond with substituted benzene ring

Photoinduced reactions of chloranil (CA) with 1,1-diarylethenes 1 [(p-X- Ph)2C=CH2, X = F, Cl, H, Me] in benzene afforded products 4-14, respectively, with the bicyclo[4.2.0]oct-3-ene-2,5-diones 4, the 6- diarylethenylcyclohexa-2,5-diene-1,4-diones 5, and 2,3,5,6- tetrachlorohydroquinone 13 as the major primary products. The cyclobutane products 4 are formed via a triplet diradical intermediate without involvement of single electron transfer (SET) between the two reactants, while 5 is derived from a reaction sequence with initial SET interaction between 3CA* and the alkene. The 9-arylphenanthrene-1,4-diones 6 and its 10-hydroxy-derivatives 7 are secondary photochemical products derived from 5. The isomeric cage products 9-11 are formed from 4 via intramolecular benzene- alkene [2 + 2] (ortho-)photocycloadditions induced by the triplet excited enedione moiety. The relative amount of the two groups of products (4 and its secondary products 9-11 via non-SET route vs 5 and its secondary products 6, 7, 8, 12, and 14 via SET route) shows a rather regular change, with the ratio of non-SET route products gradually increasing with the increase in oxidation potential of the alkenes and in the positive free energy change for electron transfer (ΔG(ET)) between 3CA* and the alkene, at the expense of the ratio of the products from the SET route. The competition between the SET and non- SET routes was also found to be drastically influenced by solvent polarity, with the SET pathways more favored in polar solvent. Photo-CIDNP investigations suggest the intermediacy of exciplexes or contact ion radical pairs in these reactions in benzene, while in acetonitrile, SET process led to the formation of CA·- and cation radical of the alkene in the form of solvent separated ion radical pairs and free ions.

Pentachlorophenol hydroxylase, a poorly functioning enzyme required for degradation of pentachlorophenol by sphingobium chlorophenolicum

Several strains of Sphingobium chlorophenolicum have been isolated from soil that was heavily contaminated with pentachlorophenol (PCP), a toxic pesticide introduced in the 1930s. S. chlorophenolicum appears to have assembled a poorly functioning pathway for degradation of PCP by patching enzymes recruited via two independent horizontal gene transfer events into an existing metabolic pathway. Flux through the pathway is limited by PCP hydroxylase. PCP hydroxylase is a dimeric protein that belongs to the family of flavin-dependent phenol hydroxylases. In the presence of NADPH, PCP hydroxylase converts PCP to tetrachlorobenzoquinone (TCBQ). The kcat for PCP (0.024 s -1) is very low, suggesting that the enzyme is not well evolved for turnover of this substrate. Structure-activity studies reveal that substrate binding and activity are enhanced by a low pKa for the phenolic proton, increased hydrophobicity, and the presence of a substituent ortho to the hydroxyl group of the phenol. PCP hydroxylase exhibits substantial uncoupling; the C4a-hydroxyflavin intermediate, instead of hydroxylating the substrate, can decompose to produce H2O2 in a futile cycle that consumes NADPH. The extent of uncoupling varies from 0 to 100% with different substrates. The extent of uncoupling is increased by the presence of bulky substituents at position 3, 4, or 5 and decreased by the presence of a chlorine in the ortho position. The effectiveness of PCP hydroxylase is additionally hindered by its promiscuous activity with tetrachlorohydroquinone (TCHQ), a downstream metabolite in the degradation pathway. The conversion of TCHQ to TCBQ reverses flux through the pathway. Substantial uncoupling also occurs during the reaction with TCHQ.

Synthesis of 2,4-Diarylquinoline Derivatives via Chloranil-Promoted Oxidative Annulation and One-Pot Reaction

An oxidative annulation for the synthesis of 2,4-diarylquinolines from o -allylanilines is disclosed that uses recyclable reagent Chloranil as the oxidant. The corresponding products are obtained in moderate to excellent yields. Furthermore, a one-pot access to 2,4-di aryl quinolines from easily available anilines and 1,3-diarylpropenes is described as a highly atom-efficient protocol that involves oxidative coupling, rearrangement, and oxidative annulation.

1-Methyl-1,4-cyclohexadiene as a Traceless Reducing Agent for the Synthesis of Catechols and Hydroquinones

Pro-aromatic and volatile 1-methyl-1,4-cyclohexadiene (MeCHD) was used for the first time as a valid H-atom source in an innovative method to reduce ortho or para quinones to obtain the corresponding catechols and hydroquinones in good to excellent yields. Notably, the excess of MeCHD and the toluene formed as the oxidation product can be easily removed by evaporation. In some cases, trifluoroacetic acid as a catalyst was added to obtain the desired products. The reaction proceeds in air and under mild conditions, without metal catalysts and sulfur derivatives, resulting in an excellent and competitive method to reduce quinones. The mechanism is attributed to a radical reaction triggered by a hydrogen atom transfer from MeCHD to quinones, or, in the presence of trifluoroacetic acid, to a hydride transfer process.

HIGH-AND LOW-POTENTIAL, WATER-SOLUBLE, ROBUST QUINONES

Substituted hydroquinones, 1,4-quinones, catechols, 1,2-quinones, anthraquinones, and anthrahydroquinones are disclosed herein. The substituted hydroquinones and catechols have the formula: while the substituted 1,4-quinones or 1,2-have the corresponding oxidized structure (1,4- benzoquinones and 1,2-benzoquinones). One or more of R1, R2, R3 and R4 include a sulfonate moiety, a sulfonimide moiety, or a phosphonate moiety, and any of R1, R2, R3 and R4 that do not include one of these moieties include an alkyl, a cycloalkyl, a thioether, a sulfoxide, a sulfone, a haloalkyl, a halogen, a nitrile, an imide, a pyrazole, or combinations thereof. The substituted anthraquinones have the formula: while the substituted anthrahydroquinones have the corresponding reduced structure. One or more of R1-R8 have a sulfonate or phosphate tethered to the ring by a thi other, amine, or ether including one or more alkyl groups. Any of R1-R8 that do not contain one of these moieties include an alkyl, a cycloalkyl, a thiother, a sulfoxide, a sulfone, a haloalkyl, a halogen, a hydroxyl, an alkoxyl, an ether, an amine, or hydrogen The substituted hydroquinones, 1,4-quinones, catechols, 1,2-quinones, anthraquinones, or anthrahydroquinones are soluble in water, stable in aqueous acid solutions, and have useful reduction potentials in the oxidized form. Accordingly, they can be used as redox mediators in emerging technologies, such as in mediated fuel cells or organic-mediator flow batteries.

Calix[4]pyrrole Hydridosilicate: The Elusive Planar Tetracoordinate Silicon Imparts Striking Stability to Its Anionic Silicon Hydride

Anionic hydridosilicates are highly reactive and strong hydride donors. In contrast, calix[4]pyrrole hydridosilicate is an entirely water-stable, anionic silicon hydride, which does not show hydridic reactivity. However, it still acts as an electron donor and enables the detection of a single electron transfer process in the reduction chemistry with hydridosilicates. Most important, these unusual properties are imparted by the unique planar structure of its elusive parent neutral silane-substantiating the effect of planar tetracoordinate silicon for the first time.

Metal-Free Oxidative C-C Coupling of Arylamines Using a Quinone-Based Organic Oxidant

A variety of arylamines are shown to undergo oxidative C-C bond formation using quinone-based chloranil/H+ reagent as the recyclable organic (metal-free) oxidant system to afford benzidines/naphthidines. Arylamines (3°/2°) designed with various substituents were employed to understand the steric as well as electronic preferences of oxidative dimerization, and a mechanism involving amine radical cation has been proposed. The tetraphenylbenzidine derivative obtained via oxidative C-C coupling has been further converted to blue-emissive hole-transporting material via a simple chemical transformation. This study highlights the preparation of novel HTMs in a simple, economic, and efficient manner.

Diels-Alder trapping of in situ generated dienes from 3,4-dihydro-2H-pyran with p-quinone catalysed by p-toluenesulfonic acid

This comprehensive study portrays that p-toluenesulfonic acid is a more efficient catalyst for the reaction between p-quinones and 3,4-dihydro-2H-pyran, than the Lewis acids. The products were accomplished by the Diels-Alder cycloaddition reaction and their mechanistic pathways have been formulated. The impact of C2 and C2,5 substituents of the p-quinones on the cycloaddition reaction has been explored. Remarkably, it is the first report to explore this kind of in situ generated diene for the Diels-Alder cycloaddition reaction.

Effect of oxalate and pH on photodegradation of pentachlorophenol in heterogeneous irradiated maghemite System

Photochemical degradation in the system of iron oxides and oxalic acid (OX) is the important reaction for detoxification of organic pollutants in natural environments, including surface soils, surface water, and even aerosols, and it was more effective at low pH according to previous studies. However, in this study, the photodegradation of pentachlorophenol (PCP) proceeded rapidly at different pH conditions in the system with maghemite and OX under UV light illumination. It was observed that the removal of PCP was 77.7% ± 0.90%, 79.9% ± 0.80% and 74.3% ± 1.50% at initial pH of 3.5, 5.0 and 7.0, respectively. To explore the degradation mechanism, the interaction of OX and maghemite were systematically studied as a function of pH. The presence of OX of 1.2 mM effectively decreased the iso-electric point (iep) of the maghemite from 5.6 to 1.8. The maximum adsorption amount of maghemite adsorbing OX increased with increasing pH value from 208 mmol kg-1 at pH = 3.5 to 293 mmol kg-1 at pH = 9.0. However, PCP (0.0375 mM) inhibited the adsorption of oxalic acid at pH = 3.5 and pH = 5.0 but promoted it at pH = 7.0 and pH = 9.0. When the initial content of OX was 1.2 mM, the highly active compounds of Fe(C2O4)33- as Fe(III) and Fe(C2O4)22- as Fe(II) were the dominant species at different pH. The formation of H2O2 also relied on the value of pH and the concentration range of H2O2 during PCP degradation was 0-1.67 mg L-1, 0-1.16 mg L-1 and 0-0.16 mg L-1at initial pH of 3.5, 5.0 and 7.0, respectively. The low pH conditions favored the iron cycling, the H2O2 generation and the broken of aromatic ring of PCP, so as to enhance the degradation rates of PCP. At the high pH conditions, due to the slowdown of the iron cycling and the decreased amount of H2O2 formation, the direct photolysis was responsible for the enhanced degradation of PCP. The foundation of high photochemical efficiencies of OX and maghemite for PCP degradation at large-scale pH conditions improves the photochemical mechanisms of OX-iron oxide system and is of important for understanding the transformation of organic pollutants in light environments.