The oxidation of p-substituted phenols with t-BuOOH in the presence of heteropolyacids was carried out. 4-t-Butylperoxy-2,5-cyclohexadien-1-ones were obtained in good yields by the oxidation of 2,4,6-trialkylsubstituted phenols in this oxidation system.
Controlling the Catalytic Aerobic Oxidation of Phenols
作者:Kenneth Virgel N. Esguerra、Yacoub Fall、Laurène Petitjean、Jean-Philip Lumb
DOI:10.1021/ja501789x
日期:2014.5.28
The oxidation of phenols is the subject of extensive investigation, but there are few catalyticaerobic examples that are chemo- and regioselective. Here we describe conditions for the ortho-oxygenation or oxidative coupling of phenols under copper (Cu)-catalyzed aerobic conditions that give rise to ortho-quinones, biphenols or benzoxepines. We demonstrate that each product class can be accessed selectively
酚类的氧化是广泛研究的主题,但很少有具有化学和区域选择性的催化需氧实例。在这里,我们描述了在铜 (Cu) 催化的有氧条件下苯酚的正氧化或氧化偶联的条件,这些条件会产生邻醌、双酚或苯并氧杂环庚烷。We demonstrate that each product class can be accessed selectively by the appropriate choice of Cu(I) salt, amine ligand, desiccant and reaction temperature. 此外,我们评估了取代基对苯酚的影响,并证明了它们对原氧化和氧化偶联途径之间选择性的影响。
Efficient Microwave Method for the Oxidative Coupling of Phenols
作者:Sharday Grant-Overton、Joshua A. Buss、Eva H. Smith、Elisa G. Gutierrez、Eric J. Moorhead、Vivian S. Lin、Anna G. Wenzel
DOI:10.1080/00397911.2014.956370
日期:2015.2
GRAPHICAL ABSTRACT Abstract: The tert-butyl peroxide–initiated, oxidativecoupling of phenols can frequently promote reactions that otherwise perform poorly under alternative conditions. Despite this utility, peroxide coupling reactions employing conventional heat often require high-dilution conditions, multiple additions of oxidant, and long reflux times, while regularly affording only moderate product
Counterion-Enhanced Pd/Enamine Catalysis: Direct Asymmetric α-Allylation of Aldehydes with Allylic Alcohols by Chiral Amines and Achiral or Racemic Phosphoric Acids
catalytic procedure for the direct asymmetric α-allylation of branched aldehydes. The use of simple chiralamines and easily prepared achiral or racemic phosphoric acids, together with a suitable Pd-source resulted in a highly active and enantioselectivecatalyst system for the allylation of various α-branched aldehydes with different allylic alcohols. The reported procedure could provide an easy access to
Solvent‐Dependent Facile Synthesis of Diaryl Selenides and Biphenols Employing Selenium Dioxide
作者:Thomas Quell、Michael Mirion、Dieter Schollmeyer、Katrin M. Dyballa、Robert Franke、Siegfried R. Waldvogel
DOI:10.1002/open.201500206
日期:2016.4
structures by the use of selenium dioxide, a stable, powerful, and commercially available oxidizer. Our new, and easy to perform protocol gives rise to biphenols and diaryl selenides depending on the solvent employed. Oxidative treatment of phenols in acetic acid yields the corresponding biphenols, whereas conversion in pyridine results in the preferred formation of diaryl selenides. As a consequence, we