95-87-4Relevant articles and documents
Mediated electron transfer with monooxygenases - Insight in interactions between reduced mediators and the co-substrate oxygen
Tosstorff, Andreas,Dennig, Alexander,Ruff, Anna Jo?lle,Schwaneberg, Ulrich,Sieber, Volker,Mangold, Klaus-Michael,Schrader, Jens,Holtmann, Dirk
, p. 51 - 58 (2014)
One of the most important obstacles to overcome in biocatalysis with monooxygenases is the enzyme's dependency on the costly redox cofactor NAD(P)H. Electrochemical regeneration systems, in which an electrode serves as electron donor, provide an alternative route to enzymatic redox reactions. Mediators are often used to accelerate electron transfer between electrode and enzyme. We investigated the mediated bioelectrochemical conversion of p-xylene to 2,5-dimethylphenol (2,5-DMP) by a P450 BM3 variant and were able to produce 2,5-DMP electrochemically. Due to the fact that mediator reduction is limited by the electrode surface a scale-up was performed. However, increasing the electrode surface area to reactor volume ratio led to a drastic increase in cathodic oxygen reduction, causing a drop in product formation. It was shown that reduced cobalt sepulchrate reacts with the co-substrate oxygen. Furthermore, the reportedly oxygen stable mediator [Cp*Rh(I)(bpy)H] + was compared to cobalt sepulchrate. While its turnover frequency is of comparable magnitude to cobalt sepulchrate when transferring the electrons between electrode and enzyme, using NADP+ as intermediary between the mediator and the enzyme significantly increased the mediator's turnover frequency. The rhodium mediator [Cp*Rh(I)(bpy)H]+ does not appear to be significantly more oxygen stable.
Reaction of hydroxyl radical with arenes in solution—On the importance of benzylic hydrogen abstraction
Waggoner, Abygail R.,Abdulrahman, Yahya,Iverson, Alexis J.,Gibson, Ethan P.,Buckles, Mark A.,Poole, James S.
, (2021/08/27)
The regioselectivity of hydroxyl radical reactions with alkylarenes was investigated using a nuclear magnetic resonance (NMR)-based methodology capable of trapping and quantifying addition and hydrogen abstraction products of the initial elementary step of the oxidation process. Abstraction products are relatively minor components of the product mixtures (15–30 mol%), depending on the magnitude of the overall rate coefficient and the number of available hydrogens. The relative reactivity of addition at a given position on the ring depends on its relation to the methyl substituents on the hydrocarbons under study. The reactivity enhancements for disubstituted and trisubstituted rings are approximately additive under the conditions of this study.
Environmentally friendly preparation method for 2,5-dimethylphenol
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Paragraph 0051-0061, (2019/02/13)
The invention relates to an environmentally friendly preparation method for 2,5-dimethylphenol. The preparation method uses 2,5-dimethyl isopropylbenzene as an initial raw material, and obtains 2,5-(dimethyl)phenyl isopropyl peroxide through air or oxygen oxidation under the action of a solvent and a composite catalyst; and 2,5-dimethylphenol can be obtained through direct rearrangement of the obtained peroxide under an acidic condition. The preparation method is cheap and easy in raw material obtaining, convenient in operation, good in reaction selectivity and high in product yield; and by-product acetone can be produced while the 2,5-dimethylphenol is prepared, so that the preparation method is high in reaction atomic economy, less in the three wastes (waste gas, waste water and industrial residue), and low in product cost.