26547-64-8

Usage

Uses

Used in Pharmaceutical Development:
2,6-dimethoxysemiquinone radicals are utilized as potential drug targets due to their involvement in redox reactions, which are crucial in various biological processes. Their high reactivity makes them valuable in the development of new therapeutic agents that can modulate these reactions for treating diseases.
Used in Environmental Remediation:
In environmental applications, 2,6-dimethoxysemiquinone radicals serve as key agents in the degradation of organic pollutants. Their participation in redox reactions facilitates the breakdown of harmful substances, contributing to environmental cleanup efforts and pollution control.
Used in Chemical Research:
2,6-dimethoxysemiquinone radicals are employed as intermediates in chemical reactions for studying the mechanisms of redox processes. Their reactivity provides a basis for understanding electron transfer reactions and the behavior of radicals in chemical systems, advancing knowledge in the field of chemistry.
Used in Material Science:
The unique properties of 2,6-dimethoxysemiquinone radicals, such as their redox activity and reactivity, make them candidates for the development of new materials with specific electronic or catalytic properties. They can be incorporated into the design of materials for energy storage, sensors, or catalysts, enhancing their performance and functionality.

Upstream product

• 93-59-4 Perbenzoic acid 
• 621-23-8 1,2,3-trimethoxybenzene 
• 67-66-3 chloroform 
• 500-99-2 3,5-dimethoxyphenol 
• 100727-40-0 nitric acid benzhydryl ester 
• 6766-82-1 4-n-propylsyringol 
• 634-36-6 1,2,3-trimethoxybenzene 
• 15233-65-5 2,6-dimethoxy-1,4-hydroquinone 
• 642-71-7 3,4,5-trimethoxyphenol 
• 14059-92-8 4-ethylsyringol 
• 20032-71-7 4-Amino-3,5-dimethoxy-phenol 
• 871896-63-8 α-Oxy-2.4.6.3'.4'-pentamethoxy-ditan 
• 530-57-4 3,5-dimethoxy-4-hydroxybenzoic acid 
• 546-67-8 lead(IV) tetraacetate 

Downstream Products

• 5691-55-4 2,6-dimethoxy-3,5-dimethyl-1,4-benzoquinone 
• 15072-32-9 2-ethyl-3,5-dimethoxy-[1,4]benzoquinone 
• 105004-07-7 3,5-dimethoxy-2-propyl-[1,4]benzoquinone 
• 19334-43-1 2,6-dimethyl-1,4-phenylene diacetate 
• 2215-96-5 4-hydroxy-3,5-dimethoxy-4-(2-oxopropyl)-cyclohexa-2,5-dienone 
• 100868-53-9 2,6-bis-dimethylamino-[1,4]benzoquinone 
• 99982-15-7 2,5-bis-dimethylamino-3-methoxy-[1,4]benzoquinone 
• 66597-02-2 6,10-dimethoxy-3-(2,4,6-trimethyl-phenyl)-1,4-dioxa-2-aza-spiro[4.5]deca-2,6,9-trien-8-one 
• 25762-79-2 2,6-diethoxy-p-benzoquinone 
• 33070-41-6 2,6-dimethoxy-p-benzosemiquinone radical 
• 19628-74-1 2,6-Dimethoxy-nitrosophenol 
• 29137-73-3 (1-Hydroxy-2,6-dimethoxy-4-oxo-cyclohexa-2,5-dienyl)-methoxy-acetic acid ethyl ester 
• 113510-82-0 C₂₂H₂₀N₂O₆ 
• 98545-82-5 2,6-dibromo-3,5-dimethoxy-hydroquinone 

Relevant academic research and scientific papers

Catalytic oxidation of para-substituted phenols with cobalt-Schiff base complexes/O2 - Selective conversion of syringyl and guaiacyl lignin models to benzoquinones

Models of guaiacyl (G) and syringyl (S) subunits in lignin have been catalytically oxidized to their corresponding p-quinones in the presence of molecular oxygen. The oxidation of syringyl-like phenols readily occurred with 5-coordinate cobalt catalysts on which one of the ligands is a monodentate pyridine or imidazole base that coordinates axially to the metal. Formation of p-quinones with this system depends on the coordination of the axial base to the metal as influenced by its pKa and its size. The yield of p-quinones from guaiacyl models was markedly improved by the addition of a sterically hindered aliphatic nitrogen base that does not coordinate to the catalyst. A mechanism involving deprotonation of the phenol substrate by the bulky base is proposed.

Synthesis of 3-O-methylgallic acid a powerful antioxidant by electrochemical conversion of syringic acid

Background A kinetic study of the electrochemical oxidation of syringic acid (3,5-dimethoxy-4-hydroxybenzoic acid) by cyclic voltammetry at treated gold disk was combined with results of electrolyses at Ta/PbO2 anode in order to convert it into potentially high-added-value product. Methods The electrochemical oxidation of syringic acid was carried out in order to convert this compound to 3-O-methylgallic acid. This latter was identified by mass spectrophotometry using LC-MS/MS apparatus. The 3-O-methylgallic acid synthesis was controlled by cyclic volammetry, Ortho-diphenolicdeterminations and DPPH radical-scavenging activity. Results The proposed mechanism is based on the hypothesis of a bielectronic discharge of syringic acid molecule under free and adsorbed form involving two intermediate cation mesomers. Hydrolysis of the more stable of this last one leads to the formation of the 3,4-dihydroxy-5- methoxybenzoic acid (3-O-methylgallic acid) as a major product. The latter aromatic compound was synthesized by anodic oxidation of syringic acid at PbO2 electrode. The cyclic voltammogram of the electrolysis bath of syringic acid shows that the anodic peak potential of 3-O-methylgallic acid was lower (E pa = 128 mV) than that of SA (Epa = 320 mV). And the strongest antiradical activity was detected when the 3-O-methylgallic acid concentration was higher . Conclusion The electrochemical oxidation using PbO2 anode is a rapid, simple and efficient method tool for a conversion of SA into 3-O-methylgallic acid, a potent antioxidant derivative General Significance The electrochemical process consists in a simple transformation of the syringic acid into 3-O-methylgallic acid having a better antioxidant capacity. This result has been justified by cyclic voltametry which shows that anodic peak of 3-O-methylgallic acid is reversible. Furthermore, its potential is lower than that of the irreversible anodic peak of syringic acid to 3-O-methylgallic acid.

Improved manganese-oxidizing activity of DypB, a peroxidase from a lignolytic bacterium

DypB, a dye-decolorizing peroxidase from the lignolytic soil bacterium Rhodococcus jostii RHA1, catalyzes the peroxide-dependent oxidation of divalent manganese (Mn2+), albeit less efficiently than fungal manganese peroxidases. Substitution of Asn246, a distal heme residue, with alanine increased the enzyme's apparent kcat and kcat/K m values for Mn2+ by 80- and 15-fold, respectively. A 2.2 A resolution X-ray crystal structure of the N246A variant revealed the Mn2+ to be bound within a pocket of acidic residues at the heme edge, reminiscent of the binding site in fungal manganese peroxidase and very different from that of another bacterial Mn2+-oxidizing peroxidase. The first coordination sphere was entirely composed of solvent, consistent with the variant's high Km for Mn2+ (17 ± 2 mM). N246A catalyzed the manganese-dependent transformation of hard wood kraft lignin and its solvent-extracted fractions. Two of the major degradation products were identified as 2,6-dimethoxybenzoquinone and 4-hydroxy-3,5-dimethoxybenzaldehyde, respectively. These results highlight the potential of bacterial enzymes as biocatalysts to transform lignin.

Synthesis of coenzyme Q0 through divanadium-catalyzed oxidation of 3,4,5-trimethoxytoluene with hydrogen peroxide

The selective oxidation of methoxy/methyl-substituted arenes to the corresponding benzoquinones has been first realized using aqueous hydrogen peroxide as a green oxidant, acid tetrabutylammonium salts of the γ-Keggin divanadium-substituted phosphotungstate [γ-PW10O38V2(μ-O)2]5- (I) as a catalyst, and MeCN as a solvent. The presence of the dioxovanadium core in the catalyst is crucial for the catalytic performance. The reaction requires an acid co-catalyst or, alternatively, a highly protonated form of I can be prepared and employed. The industrially relevant oxidation of 3,4,5-trimethoxytoluene gives 2,3-dimethoxy-5-methyl-1,4-benzoquinone (ubiquinone 0 or coenzyme Q0, the key intermediate for coenzyme Q10 and other essential biologically active compounds) with 73% selectivity at 76% arene conversion. The catalyst retains its structure under turnover conditions and can be easily recycled and reused without significant loss of activity and selectivity.

Photocatalytic Chemoselective C-C Bond Cleavage at Room Temperature in Dye-Sensitized Photoelectrochemical Cells

Selective cleavage of C-C bonds can be a valuable tool for various applications including polymer degradation and biomass utilization. Performing chemical transformations involving C-C bond cleavage steps under mild conditions and ambient temperature remains challenging due to the high dissociation energies of the C-C bond. This fundamental challenge can be solved by coupling a dye-sensitized photoelectrochemical cell (DSPEC) system, that generally targets the water splitting reaction, with a hydrogen atom transfer (HAT) mediator (HAT-DSPEC). Here, we report the solar-driven selective cleavage of the C(aryl)-C(alkyl) σ-bond in lignin at ambient temperature using an HAT-DSPEC under redox-neutral conditions. The photocatalyst (bis-2,2′-bipyridine)(2,2′-bipyridine-4,4′-dicarboxylic acid)Ru(II) (RuC) adsorbed onto a TiO2 nanorod array with the length of ～1.6 μm and a rod diameter of 100 nm atop fluorine-doped tin oxide (FTO|TiO2 NRAs|RuC) film was prepared and investigated with an HAT mediator, 4-acetamido 2,2,6,6-tetramethylpiperidine-1-oxyl (ACT), in solution. Photophysical and electrochemical studies of RuC and ACT with a lignin model compound, 1-(4-hydroxy-3,5-dimethoxyphenyl)-2-(2-methoxyphenoxy) propane-1,3-diol (LMC) reveal that the metal-to-ligand charge transfer (MLCT) excited states from the RuC are efficiently quenched in the presence of ACT with LMC. The HAT-DSPEC photoanode, containing the surface-bound photocatalyst RuC at the photoanode with ACT and LMC in solution, sustained an excellent photocurrent density, significantly outperforming that with the photocatalyst RuC alone. Moreover, the chemoselective cleavage of the C(aryl)-C(alkyl) bond in the LMC at the ambient temperature was demonstrated in the HAT-DSPEC system with a remarkable photocatalytic turnover number (>3000) leading to excellent selectivity (>90%) of C-C bond cleavage under AM1.5G irradiation (1 sun, 100 mW cm-2). These results were obtained over short reaction times and mild, redox-neutral reaction conditions without the need for extended reaction time (e.g., >24 h) or high temperature that is typical of homogeneous catalytic systems. This is the first report to demonstrate that an HAT-DSPEC can serve as a viable method for performing visible-light-driven selective C-C bond cleavage at ambient temperature.

Activated zeolites and heteropolyacids: An efficient catalysts for the synthesis of triacetoxyaromatic precursors of hydroxyquinones

The Thiele-Winter reaction is of interest for synthesis of triacetoxyaromatic precursors of hydroquinones. Liquid acid such as, chlorosulfonic acid and solid acids like heteropolyacids have an efficient catalyst can effectively replace sulfuric acid in acetoxylation reaction of quinones without use of organic solvent at room temperature.

A New Easy Access to Quinones from Iron Porphyrin-catalysed Oxidation of Methoxyarenes by Magnesium Monoperoxyphthalate

Electron-rich methoxyarenes were oxidized with high yields (55-100percent) and under mild conditions to the corresponding paraquinones by magnesium monoperoxyphthalate in the presence of catalytic amounts of a water-soluble iron porphyrin; the reaction was used to prepare methoxatin.

Copper catalysts for selective c-c bond cleavage of b-o-4 lignin model compounds

The reactivity of homogeneous copper catalysts towards the selective C-C bond cleavage of both phenolic and non-phenolic arylglycerol b-aryl ether lignin model compounds has been explored. Several copper precursors, nitrogen ligands, and solvents were evaluated in order to optimize the catalyst system. Using the optimized catalyst system, copper(I) trifluoromethanesulfonate [CuACHTUNGTRENUNG(OTf)]/L/TEMPO (L=2,6-lutidine, TEMPO=2,2,6,6-tetramethyl-piperidin-1-yl-oxyl), aerobic oxidation of the non-phenolic b-O-4 lignin model compound proceeded with good selectivity for Ca-Cb bond cleavage, affording 3,5-dimethoxybenzaldehyde as the major product. Aerobic oxidation of the corresponding phenolic b-O-4 lignin model proceeded with different selectivity, affording 2,6-dimethoxybenzoquinone and a,b-unsaturated aldehyde products resulting from cleavage of the CaCaryl bond. At low catalyst concentrations, however, a change in selectivity was observed as oxidation of the benzylic secondary alcohol predominated with both substrates.

Molecular and biochemical characterization of a new thermostable bacterial laccase from Meiothermus ruber DSM 1279

A new laccase gene (mrlac) from Meiothermus ruber DSM 1279 was successfully overexpressed to produce a laccase (Mrlac) in soluble form in Escherichia coli during simultaneous overexpression of a chaperone protein (GroEL/ES). Without the GroEL/ES protein, the Mrlac overexpressed in E. coli constituted a huge amount of the total cellular protein, but the enzyme was localized in the insoluble fraction with no activity in the soluble fraction. Co-expression of the Mrlac with the E. coli GroEL/ES drastically improved proper folding and expression of active Mrlac in the soluble fraction. Spectroscopic analysis of the purified enzyme by UV/visible and electron paramagnetic resonance spectroscopy confirmed that the Mrlac was a multicopper oxidase. The Mrlac had a molecular weight of ～50 kDa and exhibited activity towards the canonical laccase substrates 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), syringaldazine (SGZ), and 2,6-dimethoxyphenol (2,6-DMP). Kinetic constants Km and kcat were 27.3 μM and 325 min-1 on ABTS, 4.2 μM and 106 min-1 on SGZ, and 3.01 μM and 115 min-1 on 2,6-DMP, respectively. Maximal enzyme activity was achieved at 70°C with ABTS as substrate. In addition, Mrlac exhibited a half-life for deactivation at 70°C and 75°C of about 120 min and 67 min, respectively, indicating that the Mrlac is intrinsically thermostable. Finally, Mrlac was efficient in catalyzing the removal of 2,4-dichlorophene (DCP) in aqueous solution, a trait which makes the enzyme potentially useful for environmentally friendly applications.

Oxidative Dearomatization of Phenols and Polycyclic Aromatics with Hydrogen Peroxide Triggered by Heterogeneous Sulfonic Acids

We report herein a method for the oxidative dearomatization of phenols and bare polycyclic arenes into the corresponding quinoid derivatives using hydrogen peroxide. The reaction is catalyzed by sulfonic acids and best results were achieved using heterogenized species. The best results using phenols were achieved using a hybrid material, namely a perfluorinated polymer functionalized with sulfonic acid groups supported on silica. The dearomatization of polycyclic aromatic hydrocarbons performed better using the polymeric acid catalyst. These methods operate under mild conditions, using mild and benign oxidants and thus minimizing the formation of waste.