15233-65-5

Usage

Uses

Used in the Cosmetics Industry:
2,6-Dimethoxyhydroquinone is used as an additive in the preparation of modified fraxinol glycoside for sunscreen isolation cream. Its presence in the formulation enhances the cream's effectiveness in protecting the skin from harmful UV rays, thus contributing to its sun protection factor (SPF) and overall performance.
The compound's ability to absorb UV radiation and its compatibility with other ingredients make it a suitable candidate for inclusion in a wide range of cosmetic products, particularly those designed to shield the skin from the sun's damaging effects.

InChI:InChI=1/C8H10O4/c1-11-6-3-5(9)4-7(12-2)8(6)10/h3-4,9-10H,1-2H3

Upstream product

• 530-55-2 2,6-dimethoxy-p-quinone 
• 530-57-4 3,5-dimethoxy-4-hydroxybenzoic acid 
• 500-99-2 3,5-dimethoxyphenol 
• 29137-73-3 (1-Hydroxy-2,6-dimethoxy-4-oxo-cyclohexa-2,5-dienyl)-methoxy-acetic acid ethyl ester 
• 33070-41-6 2,6-dimethoxy-p-benzosemiquinone radical 
• 134-96-3 syringic aldehyde 
• 91-10-1 1,3-dimethoxy-2-hydroxy-benzene 
• 634-36-6 1,2,3-trimethoxybenzene 
• 6766-82-1 4-n-propylsyringol 
• 2478-38-8 1-(4-hydroxy-3,5-dimethoxy-phenyl)-ethanone 
• 92409-34-2 1-(4-hydroxy-3,5-dimethoxyphenyl)-2-(2'-methoxyphenoxy)-1,3-propanediol 

Downstream Products

• 857564-76-2 3,6-dihydroxy-2,4-dimethoxy-deoxybenzoin 
• 857564-80-8 3,6-dihydroxy-2,4,4'-trimethoxy-deoxybenzoin 
• 72461-22-4 4-ethoxy-3,5-dimethoxy-phenol 
• 105342-72-1 3,6-diethoxy-2-hydroxy-4-methoxyacetophenone 
• 105827-22-3 3,6-dihydroxy-2,4-dimethoxybenzaldehyde 
• 530-55-2 2,6-dimethoxy-p-quinone 
• 61014-67-3 2,6-dibromo-3,5-dimethoxy-1,4-benzoquinone 
• 7702-17-2 4-(acetyloxy)-3,5-dimethoxyphenyl acetate 
• 500299-17-2 2-chloro-1-(3,6-dihydroxy-2,4-dimethoxy-phenyl)-ethanone 
• 642-71-7 3,4,5-trimethoxyphenol 
• 5333-45-9 1,2,3,5-tetramethoxybenzene 
• 108971-85-3 6-hydroxy-5,7-dimethoxy-4-phenyl-coumarin 
• 78151-59-4 2,2',4,4'-tetramethoxydiphenylmethane-3,3',6,6'-tetrol 
• 141017-75-6 1,3-Dimethoxy-2,5-bis-trimethylsilanyloxy-benzene 

Relevant academic research and scientific papers

Glycosides from the stem bark of Fraxinus sieboldiana

A norditerpene glucopyranoside with a novel carbon skeleton (1), eight new aromatic glycosides (2-9), and 25 known glycosides have been isolated from a H2O-soluble portion of an ethanolic extract of the stem bark of Fraxinus sieboldiana. Their structures were determined by spectroscopic and chemical methods. Based on analysis of the NMR data of threoand erythro-arylglycerols in different solvents, an application of Δδ5C8-C7 values to distinguish threo-arylglycerol and erythro-arylglycerol isomers was proposed. In the in vitro assays, compound 5 displayed TNF-α secretion inhibitory activity with an IC50 value of 1.6 μM, compound 6 showed antioxidative activity inhibiting Fe +2-cystine-induced rat liver microsomal lipid peroxidation with an IC50 value of 0.9 μM, and plantasioside (10) showed selective activity against the human colon cancer cell line (HCT-8) with an IC 50 value of 3.4 μM.

Determining Proton-Coupled Standard Potentials and X-H Bond Dissociation Free Energies in Nonaqueous Solvents Using Open-Circuit Potential Measurements

Proton-coupled electron transfer (PCET) reactions are increasingly being studied in nonaqueous conditions, where the thermochemistry of PCET substrates is largely unknown. Herein, we report a method to obtain electrochemical standard potentials and calculate the corresponding bond dissociation free energies (BDFEs) of stable PCET reagents in nonaqueous solvents, using open-circuit potential (OCP) measurements. With this method, we measure PCET thermochemistry in acetonitrile and tetrahydrofuran for substrates with O-H and N-H bonds that undergo 1e-/1H+ and 2e-/2H+ redox processes. We also report corrected thermochemical values for the 1/2H2(g)/H?1M and H+/H? (CG) couples in several organic solvents. For 2e-/2H+ couples, OCP measurements provide the multielectron/multiproton standard potential and the average of the two X-H BDFEs. In contrast to traditional approaches for calculating BDFEs from electrochemical measurements, the OCP method directly measures the overall PCET reaction thermodynamics and avoids the need for a pKa scale in the solvent of interest. Consequently, the OCP approach yields more accurate thermochemical values and should be general to any solvent mixture compatible with electrochemical measurements. The longer time scale of OCP measurements enables accurate thermochemical measurements for redox couples with irreversible or distorted electrochemical responses by cyclic voltammetry, provided the PCET reaction is chemically reversible. Recommendations for successful OCP measurements and limitations of the approach are discussed, including the current inability to measure processes involving C-H bonds. As a straightforward and robust technique to determine nonaqueous PCET thermochemistry, these OCP measurements will be broadly valuable, with applications ranging from fundamental reactivity studies to device development.

A practical synthesis of the flavone, scutellarein

A practical and economical five-step synthesis of the flavone scutellarein has been achieved in 60% overall yield using the available and cheap 2,6-dimethoxy-1,4-benzoquinone as starting material. The reaction sequence involved reduction to the corresponding quinol, Friedel-Crafts acetylation, Claisen-Schmidt condensation with p-methoxybenzaldehyde, cyclisation and demethylation. The procedure is operationally simple and amenable to scale-up synthesis.

Understanding factors controlling depolymerization and polymerization in catalytic degradation of β-ether linked model lignin compounds by versatile peroxidase

Lignin is a major component of lignocellulosic biomass and is responsible for much of its recalcitrant nature. Enzymatic breakdown of lignin into valuable products potentially represents an additional revenue stream in biofuels production. Many enzymes have been characterized which perform oxidative catalysis of lignin decomposition. However, the nature of the decomposition products from a given enzyme-catalyzed reaction depends on competition between depolymerization of lignin and repolymerization of the resulting depolymerization products, resulting in either polymeric products or small, aromatic species. The latter have greater value, as aromatic monomers can be used as precursors in the production of fuels and specialty chemicals via chemical or synthetic biological routes. An understanding of the factors that control the equilibrium between depolymerization and polymerization remains elusive. In this study we investigated this equilibrium for a versatile peroxidase from B. adusta using several lignin model compounds containing β-ether bonds as substrates and characterized the effects of reaction conditions (pH, addition of H2O2 and mediators) on catalysis. In tandem, quantum chemistry calculations of free energy changes of relevant chemical reactions and of electron spin density distributions of radical species were performed. Due to the low oxidation potential of the neutral radical, this enzyme is unable to oxidize non-phenolic lignin subunits. The results indicate that for phenolic lignin dimers the versatile peroxidase first produces a neutral radical via oxidation of the 4-OH position, followed by polymerization and depolymerization reactions. Selection between polymerization and depolymerization reaction pathways was found to be dependent on the functional group at the 5 position of the guaiacyl group (G5). In the case of a hydrogen atom at the G5 position (guaiacylglycerol-β-ether), the unpaired electron is distributed between the 4-OH and G5 positions, resulting in polymerization. However, substitution of G5 with a methoxy group (S-O-4) results in roughly equal distribution of the unpaired electron at G1 and 4-OH, leading to extensive side chain cleavage. The degradation pathway of phenolic β-O-4 was identified as Cα-aryl cleavage rather than Cα-Cβ.

Series of charge transfer complexes obtained as crystals in a confined environment

A series of charge transfer complexes (CTCs) were successfully formed by solvent free processing techniques, using the 1,2,4,5-tetracyano benzene (TCNB) as πAmolecule and a series ofp-dihydroquinones (H2Qs) as πDcounterparts. Additionally to the classical co-evaporation techniques, we obtained CTCs in less than an hour, in a very simple confined environment, between two 100 μm - spaced glass plates. A systematical study by Raman spectroscopy on crystals highlighted the CTCs formation. Moreover, three new crystalline structures were obtained, namely TCNB-H2Q that crystallizes in columns connected to each other by H-bonds, while with the methoxy- and dimethoxy-H2Qs the CTC forms crystals with the stoichiometry 1?:?2, TCNB-(H2QOMe)2and TCNB-(H2QOMe2)2. In TCNB-(H2QOMe)2layers are formed due to intermolecular hydrogen bonds, while in TCNB-(H2QOMe2)2molecules arrange in triads, with πA-πDinteractions. In all cases, strong πA-πDinteractions exist with intermolecular distances lower than the van der Waals distances, which results in strong absorption bands in the visible range.

Heterogeneous Nitrogen-doped Graphene Catalysed HOO? Generation via a Non-radical Mechanism for Base-free Dakin Reaction

A heterogeneous nitrogen-doped graphene catalytic pathway for H2O2 activation to generate alkaline hydrogen peroxide (HOO?) through a non-radical mechanism was reported. Remarkably, the heterogeneous catalytic procedure has been used for the evergreen and environmentally Dakin reaction without using any transition metals, homogeneous bases, ligands, additives or promoters, completely. The study of catalyst structure and catalytic activities indicate that the most active sites are created by the graphitic N atoms at zig-zag edges of the sheets. In addition, N as dopant element changes the reactivity of the neighbour C atoms, and leads to the formation of carbon-hydroperoxide (C?(HOOH)) and C?O* (C?O?) transition state species on the graphene surface in catalytic the reaction. (Figure presented.).

Method For Producing Low Molecular Weight Aromatic Lignin-Derived Compounds

The present invention relates to a method for producing one or more low molecular weight aromatic lignin-derived compounds. The method preferably comprises providing lignocellulosic material, subjecting the lignocellulosic material to a pulping process, separating pulp to provide a substantially pulp-free process stream comprising a modified lignin-derived component, isolating the modified lignin-derived component, subjecting the isolated modified lignin-derived component to a decomposition step comprising oxidative cracking (cracking and oxidizing) or reducing under the influence of a catalyst or electro-oxidation, and subjecting the resulting products to an isolation step, to provide a low molecular weight aromatic lignin-derived compound. Said compound may be further modified, e.g. by annulation. The inventive method preferably comprises further oxidizing said compound to a redox active compound. Additionally, the present invention relates to compounds obtainable by the inventive method and to an assembly for carrying out the inventive method. Furthermore, the present invention refers to a method for providing an existing pulp and/or paper manufacturing plant with said assembly.

AMINATED LIGNIN-DERIVED COMPOUNDS AND USES THEREOF

The present invention relates to novel lignin-derived compounds and compositions comprising the same and their use as redox flow battery electrolytes. The invention further provides a method for preparing said compounds and compositions as well as a redox flow battery comprising said compounds and compositions. Additionally, an assembly for carrying out the inventive method is provided.

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.

Catalytic Electrophilic Alkylation of p-Quinones through a Redox Chain Reaction

Allylation and benzylation of p-quinones was achieved through an unusual redox chain reaction. Mechanistic studies suggest that the existence of trace hydroquinone initiates a redox chain reaction that consists of a Lewis acid catalyzed Friedel–Crafts alkylation and a subsequent redox equilibrium that regenerates hydroquinone. The electrophiles could be various allylic and benzylic esters. The addition of Hantzsch ester as an initiator improves the efficiency of the reaction.