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
Enantioselective Synthesis of Tryptophan Derivatives by a Tandem Friedel–Crafts Conjugate Addition/Asymmetric Protonation Reaction
作者:Madeleine E. Kieffer、Lindsay M. Repka、Sarah E. Reisman
DOI:10.1021/ja209390d
日期:2012.3.21
tandem Friedel-Crafts conjugate addition/asymmetric protonation reaction between 2-substituted indoles and methyl 2-acetamidoacrylate is reported. The reaction is catalyzed by (R)-3,3'-dibromo-BINOL in the presence of stoichiometric SnCl(4), and is the first example of a tandem conjugate addition/asymmetric protonation reaction using a BINOL·SnCl(4) complex as the catalyst. A range of indoles furnished
An efficient enantioselectiveoxidativecoupling of 2-naphtholderivatives based on a concept of dual activation catalysis is realized. A chiral dinuclear vanadium(IV) complex (Ra,S,S)-1e possessing (S)-tert-leucine moieties at the 3,3′-positions of the (R)-binaphthyl skeleton was developed, which was found to promote the oxidativecoupling of 2-naphthol to afford (S)-BINOL with 91% ee. To verify the
The Interrupted Pummerer Reaction in a Sulfoxide‐Catalyzed Oxidative Coupling of 2‐Naphthols
作者:Zhen He、Alexander P. Pulis、David J. Procter
DOI:10.1002/anie.201903492
日期:2019.6.3
A benzothiopheneS‐oxide catalyst, generated in situ by sulfur oxidation with H2O2, mediates the oxidative coupling of 2‐naphthols. Key to the catalytic process is the capture and inversion of reactivity of a 2‐naphthol partner, using an interrupted Pummerer reaction of an unusualbenzothiopheneS‐oxide, followed by subsequent coupling with a second partner. The new catalytic manifold has been showcased
通过H 2 O 2硫氧化原位生成的苯并噻吩S-氧化物催化剂介导2-萘酚的氧化偶联。催化过程的关键是使用不寻常的苯并噻吩S-氧化物中断的Pummerer反应,然后与第二个配偶偶合,捕获和转化2-萘酚配偶的反应性。新的催化歧管已在生物活性天然产物(±)-尼莫酮和(±)-异麦酮的合成中得到展示。尽管Pummerer反应被广泛使用,但它们在催化中的应用却很少,我们的方法代表了一种新的无金属C-C键形成的催化流形。
Metal-free carbon as a catalyst for oxidative coupling: solvent-enhanced poly-coupling with regioselectivity
作者:Melad Shaikh、Aanchal Sahu、A. Kiran Kumar、Mahendra Sahu、Sunil. K. Singh、Kalluri V. S. Ranganath
DOI:10.1039/c7gc02227a
日期:——
A heterogeneous, inexpensive and a metalfree, environmental friendly graphene oxide (GO), has been developed for the oxidative poly coupling of 2-naphthols in aqeous sodium hydroxide in the presence of air. This study found that GO could function as a heterogeneous catalyst and solvent played a vital role in the coupling. Changing of the solvent from toluene to water leads to the formation of homocoupling