824-69-1

Usage

Uses

Used in Chemical Synthesis:
2,5-Dichlorohydroquinone is used as a chemical intermediate in the synthesis of various organic compounds. Its unique structure with chloro substitutions at specific positions allows for targeted functionalization and the formation of diverse chemical products.
Used in Environmental Research:
As a degradation product of certain chlorinated compounds, 2,5-DCHQ plays a role in environmental research, particularly in understanding the fate and transformation of pollutants in the environment. This knowledge can contribute to the development of strategies for pollution control and remediation.
Used in Material Science:
The properties of 2,5-Dichlorohydroquinone, such as its crystalline nature and chemical reactivity, may find applications in material science. For instance, it could be utilized in the development of new materials with specific characteristics, such as improved stability or reactivity, for various industrial applications.

InChI:InChI=1/C6H4Cl2O2/c7-3-1-5(9)4(8)2-6(3)10/h1-2,9-10H

Upstream product

• 64-17-5 ethanol 
• 57165-98-7 2,5,6-trichloro-cyclohex-2-ene-1,4-dione 
• 615-93-0 2,5-Dichloro-1,4-benzoquinone 
• 63335-14-8 1,4-dichloro-2,5-bis-chloromethoxy-benzene 
• 695-99-8 2-Chloro-1,4-benzoquinone 
• 62-53-3 aniline 
• 123-31-9 hydroquinone 
• 1221-72-3 Bis(p-methoxyphenyl)diazomethan 
• 1143-92-6 bis-(4-chlorophenyl)diazomethane 
• 150-13-0 4-amino-benzoic acid 
• 150-76-5 4-methoxy-phenol 
• 908093-98-1 diazodiphenylmethane 
• 92-85-3 Thianthrene 
• 67-66-3 chloroform 

Downstream Products

• 67828-63-1 1,4-diethoxy-2,5-dichloro-benzene 
• 114446-88-7 1,4-bis-(10-bromo-decyloxy)-2,5-dichloro-benzene 
• 484031-67-6 (2,5-dichloro-p-phenylenedioxy)-di-acetic acid 
• 2675-77-6 1,4-dichloro-2,5-dimethoxybenzene 
• 615-93-0 2,5-dichloro-1,4-benzoquinone radical anion 
• 615-93-0 2,5-Dichloro-1,4-benzoquinone 
• 3225-29-4 p-benzosemiquinone radical anion 
• 74-31-7 N,N'-diphenyl-1,4-phenylenediamine 
• 122-37-2 4-anilinophenol 
• 134044-81-8 2,5-dichloro-4-hydroxyphenoxyl radical 
• 34865-89-9 p-hydroxydiphenylamine radical 
• 89284-69-5 2-chloro-5-hydroxy-1,4-benzoquinone 
• 71155-99-2 2,5-dichlorohydroquinone diacetate 
• 6172-33-4 1,4-diallyloxy-2,5-dichlorobenzene 

Relevant academic research and scientific papers

Mechanisms of hydride abstractions by quinones

The kinetics of the hydride abstractions by 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) from 13 C-H hydride donors (acyclic 1,4-dienes, cyclohexa-1,4-dienes, dihydropyridines), tributylstannane, triphenylstannane, and five borane complexes (amine-boranes, carbene-boranes) have been studied photometrically in dichloromethane solution at 20 °C. Analysis of the resulting second-order rate constants by the correlation log k2(20°C) = sN(E + N) (J. Am. Chem. Soc. 2001, 123, 9500) showed that the hydride abstractions from the C-H donors on one side and the Sn-H and B-H hydride donors on the other follow separate correlations, indicating different mechanisms for the two reaction series. The interpretation that the C-H donors transfer hydrogen to the carbonyl oxygen of DDQ while Sn-H and B-H hydride donors transfer hydride to a cyano-substituted carbon of DDQ is supported by quantum-chemical intrinsic reaction coordinate calculations and isotope labeling experiments of the reactions of D8-cyclohexa-1,4-diene, Bu3SnD, and pyridine·BD3 with 2,5-dichloro-p-benzoquinone. The second-order rate constants of the reactions of tributylstannane with different quinones correlate linearly with the electrophilicity parameters E of the quinones, which have previously been derived from the reactions of quinones with -nucleophiles. The fact that the reactions of Bu3SnH with quinones and benzhydrylium ions are on the same log k2 vs E (electrophilicity) correlation shows that both reaction series proceed by the same mechanism and illustrates the general significance of the reactivity parameters E, N, and sN for predicting rates of polar organic reactions.

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.

Reactivity of iPrPCPIrH4 with para-benzoquinones

In the interest of investigating new hydrogen acceptors for pincer–iridium catalyzed dehydrogenations with the ability to be catalytically recycled, a series of para-benzoquinones have been reacted with iPrPCPIrH4 in various solvents and conditions. Preliminary results indicate that a wide range of quinones are capable of dehydrogenating iPrPCPIrH4, and that several turn-overs in alcohol dehydrogenation by iPrPCPIr are possible at room temperature using benzoquinone acceptors. However, strong acceptor–catalyst interactions are inhibitory toward catalysis when the acceptor is used in excess. A new class of (bis)-η2 pi-adducts, formed between iPrPCPIr and benzoquinones, nicknamed “barber-chairs”, has been identified and 3 examples have been characterized.

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.

Kinetic mechanism of the dechlorinating flavin-dependent monooxygenase HadA

The accumulation of chlorophenols (CPs) in the environment, due to their wide use as agrochemicals, has become a serious environmental problem. These organic halides can be degraded by aerobic microorganisms, where the initial steps of various biodegradation pathways include an oxidative dechlorinating process in which chloride is replaced by a hydroxyl substituent. Harnessing these dechlorinating processes could provide an opportunity for environmental remediation, but detailed catalytic mechanisms for these enzymes are not yet known. To close this gap, we now report transient kinetics and product analysis of the dechlorinating flavin-dependent monooxygenase, HadA, from the aerobic organism Ralstonia pickettii DTP0602, identifying several mechanistic properties that differ from other enzymes in the same class. We first overexpressed and purified HadA to homogeneity. Analyses of the products from single and multiple turnover reactions demonstrated thatHadAprefers 4-CP and 2-CP over CPs with multiple substituents. Stopped-flow and rapid-quench flow experiments of HadA with 4-CP show the involvement of specific intermediates (C4a-hydroperoxy-FAD and C4a-hydroxy-FAD) in the reaction, define rate constants and the order of substrate binding, and demonstrate that the hydroxylation step occurs prior to chloride elimination. The data also identify the non-productive and productive paths of the HadA reactions and demonstrate that product formation is the rate-limiting step. This is the first elucidation of the kinetic mechanism of a two-component flavin-dependent monooxygenase that can catalyze oxidative dechlorination of various CPs, and as such it will serve as the basis for future investigation of enzyme variants that will be useful for applications in detoxifying chemicals hazardous to human health.

Cycloacylation of chloro-substituted hydroquinone dimethyl ethers with dichloromaleic anhydride

Under the drastic conditions of Zahn—Ochwat cycloacylation of 2-chloroand 2,3-dichlorohydroquinones with dichloromaleic anhydride (a melt of anhydrous AlCl3 and NaCl, 185—195 °C), the substrates undergo various degrees of disproportionation, which reduces the yields of the target triand tetrachloronaphthazarins. Quantum chemical calculations showed that the cycloacylation in question proceeds as a double aromatic electrophilic substitution of the vicinal protons with the corresponding oxocarbenium ions (acylium cations).

Characterization of chlorophenol 4-monooxygenase (TftD) and NADH:FAD oxidoreductase (TftC) of burkholderia cepacia AC1100

Burkholderia cepacia AC1100 completely degrades 2,4,5-trichlorophenol, in which an FADH2-dependent monooxygenase (TftD) and an NADH:FAD oxidoreductase (TftC) catalyze the initial steps. TftD oxidizes 2,4,5-trichlorophenol (2,4,5-TCP) to 2,5-dichloro-p-benzoquinone, which is chemically reduced to 2,5-dichloro-p-hydroquinone (2,5-DiCHQ). Then, TftD oxidizes the latter to 5-chloro-2-hydroxy-p-benzoquinone. In those processes, TftC provides all the required FADH2. We have determined the crystal structures of dimeric TftC and tetrameric TftD at 2.0 and 2.5 A resolution, respectively. The structure of TftC was similar to those of related flavin reductases. The stacked nicotinamide:isoalloxazine rings in TftC and sequential reaction kinetics suggest that the reduced FAD leaves TftC after NADH oxidation. The structure of TftD was also similar to the known structures of FADH2-dependent monooxygenases. Its His-289 residue in the re-side of the isoalloxazine ring is within hydrogen bonding distance with a hydroxyl group of 2,5-Di-CHQ.AnH289Amutation resulted in the complete loss of activity toward 2,5-DiCHQ and a significant decrease in catalytic efficiency toward 2,4,5-TCP. Thus, His-289 plays different roles in the catalysis of 2,4,5-TCP and 2,5-DiCHQ. The results support that free FADH2 is generated by TftC, and TftD uses FADH2 to separately transform 2,4,5-TCP and 2,5-DiCHQ. Additional experimental data also support the diffusion of FADH2 between TftC and TftD without direct physical interaction between the two enzymes.

Rate constants of elementary steps of the reversible chain reaction of N-phenyl-1,4-benzoquinonemonoimine with 2,5-dichlorohydroquinone

The kinetics of reversible chain reactions in quinoneimine-hydroquinone systems has first been studied for the reaction of N-phenyl-1,4- benzoquinonemonoimine with 2,5-dichloro-hydroquinone used as an example. The dependences of the reaction rate on the concentration of the initial reactants, initiator, and each product were studied. The reliable estimates of the rate constants of 11 (of 12) elementary steps of this reaction were obtained from the experimental data using the earlier derived formulas and the method of equal concentrations developed in the present work.

The kinetics of the reversible chain reaction between 2,5-dichloroquinone and 4-hydroxydiphenylamine

The paper presents the results obtained in a study of the kinetics of the reversible chain reaction between 2,5-dichloroquinone and 4-hydroxydiphenylamine (K eq = 3.2). We studied the dependence of the reaction rate on the concentrations of the initiator, initial reagents, and all products. The equations obtained earlier for the rate of reversible chain reactions and the method of equal concentrations suggested in this work were used to estimate the rate constants of most of the reaction mechanism elementary steps from the experimental data. The results obtained were shown to closely agree with and agument the data obtained earlier for the kinetics of the chain reaction between N-phenyl-1,4-benzoquinonemonoimine and 2,5-dichlorohydroquinone. On the whole, all the elementary steps of these two (forward and back) reversible chain reactions were characterized by rate constant values.

Determination of dissociation energies of N-H bond in the 4-anilinodiphenylaminyl radical and O-H bond in the 2,5-dichloro-4- hydroxyphenoxyl radical from the equilibrium constants of chain reactions in quinoneimine-hydroquinone systems

The temperature dependences of the equilibrium constants of two chain reversible reactions in quinonediimine (quinonemonoimine)-2,5- dichlorohydroquinone systems in chlorobenzene were studied. The enthalpy of equilibrium of the reversible reaction of quinonediimine with 4-hydroxydiphenylamine was estimated from these data (ΔH = - 14.4±1.6 kJ mol-1) and a more accurate value of the N-H bond dissociation energy in the 4-anilinodiphenylaminyl radical was determined (DNH = 278.6±3.0 kJ mol-1). A chain mechanism was proposed for the reaction between quinonediimine and 2,5-dichlorohydroquinone, and the chain length was estimated (ν = 300 units) at room temperature. Processing of published data on the rate constant of the reaction of styrylperoxy radicals with 2,5-dichlorohydroquinone in the framework of the intersecting parabolas method gave the O-H bond dissociation energy in 2,5-dichlorohydroquinone: DOH = 362.4±0.9 kJ mol-1. Taking into account these data, the O-H bond dissociation energy in the 2,5-dichlorosemiquinone radical was found: DOH = 253.6±1.9 kJ mol-1.