91458-98-9Relevant academic research and scientific papers
Oxidant dependent oxidation of copper bound catecholate: Catecholase versus catechol dioxygenase activity
Lakk-Bogáth, Dóra,Csonka, Róbert,Lorencz, Noémi,Giorgi, Michel,Speier, Gábor,Kaizer, József
, p. 185 - 192 (2015)
A series of new mixed ligand copper complexes CuII(PBI)(O2Ncat) (1) (PBI = 2-(2-pyridyl)-benzimidazole), CuII(DMPBI)(O2Ncat) (2) (DMPBI = 5,6-dimethyl-2-(2-pyridyl)-benzimidazole), CuII(PBO)(O2/
Synthesis and spectroscopic characterization of ternary copper(ii) complexes containing nitrogen and oxygen donors as functional mimics of catechol oxidase and phenoxazinone synthase
Abdel-Rahman, Adel A.-H.,Al-Harbi, Sami A.,Ibrahim, Mohamed M.,Omar, Walid,Ramadan, Abd El-Motaleb M.,Sallam, Shehab A.,Shaban, Shaban Y.
, p. 6331 - 6345 (2020/05/13)
Two ternary copper(ii) complexes 1 [(Cu2Me4en)4(EDTA)] and 2 [(CuMe4en)2(MIDA)] containing the mixed ligand system of 1,1′,4,4′-tetramethylethylenediamine (Me4en) (L) and N-methyliminodiace
Dearomatization of Electron-Deficient Phenols to ortho-Quinones: Bidentate Nitrogen-Ligated Iodine(V) Reagents
Xiao, Xiao,Greenwood, Nathaniel S.,Wengryniuk, Sarah E.
supporting information, p. 16181 - 16187 (2019/11/05)
Despite their broad utility, the synthesis of ortho-quinones remains a significant challenge, in particular, access to electron-deficient derivatives remains an unsolved problem. Reported here is the first general method for the synthesis of electron-deficient ortho-quinones by direct oxidation of phenols. The reaction is enabled by a novel bidentate nitrogen-ligated iodine(V) reagent, a previously unexplored class of compounds which we have termed Bi(N)-HVIs. The reaction is extremely general and proceeds with excellent regioselectivity for the ortho over para isomer. Functionalization of the ortho-quinone products was examined, resulting in a facile one-pot synthesis of catechols, as well as the incorporation of a variety of heteroatom nucleophiles. This method represents the first synthetic application of Bi(N)-HVIs and demonstrates their potential as a platform for the further development of highly reactive, but also highly tunable, I(V) reagents.
Multiple oxo-vanadium schiff base containing cyclotriphosphazene as a robust heterogeneous catalyst for regioselective oxidation of naphthols and phenols to quinones
Khatri, Praveen K.,Jain, Suman L.
, p. 1020 - 1025 (2012/10/29)
Grafting of multiple oxo-vanadium Schiff base moieties to cyclotriphosphazene provided an efficient and recyclable heterogeneous catalyst for the regioselective oxidation of naphthols and phenols to quinones by using tbutylhydroperoxide as oxidant. One of the main advantages of the developed catalyst was the presence of multiple oxovanadium moieties in close proximity which made the developed catalyst more active as compared to its homogeneous oxo-vanadium Schiff base. After the reaction, the catalyst was easily recovered from the reaction mixture by simple filtration and reused for five runs without loss in activity.
Kinetics of the Oxidation of Ascorbic Acid and Substituted 1,2- and 1,4-Dihydroxybenzenes by the Hexacyanoruthenate(III) Ion in Acidic Perchlorate Media
Hoddenbagh, J. Mark A.,Macartney, Donal H.
, p. 615 - 620 (2007/10/02)
The kinetics of oxidation of ascorbic acid and a series of substituted 1,2- and 1,4-dihydroxybenzene compounds (H2Q) by 3- have been investigated in acidic perchlorate media.The inverse dependences of the rate constants on acid concentrations for 2,3-dicyano-1,4-dihydroxybenzene, 4,5-dihydroxybenzene-1,3-disulphonate, and ascorbic acid have been attributed to concurrent rate-determining pathways involving the one-electron oxidations of H2Q or HQ(-) by 3- to the corresponding semiquinone or ascorbate radical intermediate.The cross-reaction rate constants have been correlated with the semiquinone or ascorbate reduction potentials in terms of the Marcus relationship to yield a 3--4- electron self-exchange rate constant of (1.0 +/- 0.8) . 105 dm3mol-1s-1.This is compared with those for other low-spin d5-d6 transition-metal complex couples and discussed in terms of the inner-sphere and solvent reorganization energies.
Kinetics of the Reduction of a Tetra-μ-acetato-dirhodium Cation by Substituted 1,2- and 1,4-Dihydroxybenzene Compounds in Aqueous Perchlorate Media
Herbert, John W.,Macartney, Donal H.
, p. 1931 - 1936 (2007/10/02)
The kinetics of the reduction of the tetra-μ-acetato-dirhodium cation, +(+), by substituted 1,2- and 1,4-dihydroxybenzene compounds (H2Q) have been investigated in aqueous perchlorate media.The observed rate equation (below) is interpreted in terms of a rate- -d+>/dt=2(k1+k2K1/+>)+> determining one-electron oxidation of H2Q or HQ- to a semiquinone radical intermediate.The rate constants for the cross-reactions are correlated with the semiquinone reduction potentials by means of the Marcus relationship.Self-exchange rate constants for the dihydroxybenzene/semiquinone and semiquinone/quinone couples are discussed in terms of the inner-sphere and solvent reorganization energies for electron exchange.
Kinetics and Mechanism of Oxidation of Acetanilide and para-Substituted Acetanilides by HClO4-Phenyliodosyl Acetate System
Radhakrishnamurti, P. S.,Sasmal, B. M.,Patnaik, D. P.
, p. 106 - 108 (2007/10/02)
Oxidation of acetanilide and p-methyl-, p-chloro-, p-bromo- and p-nitro-acetanilides by phenyliodosyl acetate (PIA) in the presence of HClO4 in aqueous medium is first order in and fractional order each in and .Increase in percentage of HOAc in the solvent mixture increases the rate.A probable reaction mechanism and rate law consistent with it have been discussed.
Application of Kendall's Treatment on Ru(III) Catalysed Periodate Oxidation of p-Nitrophenol, 2,4-Dinitrophenol and 2,4,6-Trinitrophenol
Radhakrishnamurti, P. S.,Damodar Rao, B. V.
, p. 487 - 489 (2007/10/02)
Ru(III) catalysed periodate oxidation of p-nitrophenol, 2,4-dinitrophenol and picric acid has been investigated in a wide range of pH from acidic to neutral in aqueous medium.The order in oxidant is zero.In acidic and neutral pH all substrates exhibit uni
Kinetics of V(IV) Catalysed Oxidation of Phenols by Acid Bromate
Parimala, N.,Lakshmi, Vijaya,Sundaram, E. V.
, p. 667 - 669 (2007/10/02)
The oxidation of phenol and substituted phenols was studied using KBrO3 as oxidant in presence of V(IV) in binary solvent mixtures of acetic acid in water.Order with respect to oxidant is one and the order with respect to substrate and the catalyst is found to be fractional.The behaviour of acid shows that the order in acid is different under different acid concentrations.Effects of temperatures and percentage composition of acetic acid were studied.A suitable mechanism in presence of catalyst is given explaining the experimental facts.The effect of substituents was also studied and discussed.
