据报道,在氟化溶剂中,FeCl 3催化酚类成分与1,3,5-三甲氧基苯的仿生氧化交叉偶联,一步合成了被保护的酚和非天然聚芳基。在这种高效转化中,区域选择性(邻位,间位或对位)和化学选择性(C C vs C O)受酚邻位键的控制-不断增长的酚类低聚物。通过将双酚衍生物与亲核芳烃偶合,以提供大的聚芳基化合物,而该聚芳基化合物不易通过其他方式获得,从而检查了反应范围。通过进行顺序氧化苯酚-苯酚和苯酚-芳烃的偶联反应,可以高效地提供单一的聚芳基产物,从而证明了催化系统在设计聚芳基骨架中的多功能性。
Selective, Catalytic, and Metal-Free Coupling of Electron-Rich Phenols and Anilides Using Molecular Oxygen as Terminal Oxidant
作者:Luis Bering、Melina Vogt、Felix M. Paulussen、Andrey P. Antonchick
DOI:10.1021/acs.orglett.8b01631
日期:2018.7.6
Selective oxidative homo- and cross-coupling of electron-rich phenols and anilides was developed using nitrosonium tetrafluoroborate as a catalyst. Oxidative coupling of phenols revealed unusual selectivities, which translated into the unprecedented synthesis of inverse Pummerer-type ketones. Mechanistic studies suggest that oxidative coupling of phenols and anilides shares a common pathway via homolytical
Solvent-controlled selective synthesis of biphenols and quinones via oxidative coupling of phenols
作者:Nagnath Yadav More、Masilamani Jeganmohan
DOI:10.1039/c7cc04829g
日期:——
A regioselective synthesis of unsymmetrical and symmetrical biphenols and binaphthols via oxidativecoupling of phenols or naphthols in the presence of K2S2O8 in CF3COOH at ambient conditions is described. Interestingly, 1:1 ratio of H2O and CH3CN solvent mixtures at 80 °C instead of CF3COOH provided substituted unsymmetrical quinones. A gram scale synthesis of biphenols and binaphthols was demonstrated
描述了在环境条件下在CF 3 COOH中在K 2 S 2 O 8存在下通过酚或萘酚的氧化偶联的不对称和对称的双酚和联萘酚的区域选择性合成。有趣的是,在80°C的H2O和CH3CN溶剂混合物以1:1的比例代替CF3COOH提供了取代的不对称醌。证明了双酚和联萘酚的克级合成。
Anodic Coupling of Guaiacol Derivatives on Boron-Doped Diamond Electrodes
作者:Axel Kirste、Gregor Schnakenburg、Siegfried R. Waldvogel
DOI:10.1021/ol201030g
日期:2011.6.17
The anodic treatment of guaiacol derivatives on boron-dopeddiamondelectrodes (BDD) provides a direct access to nonsymmetrical biphenols, which would require a multistep sequence by conventional methods. Despite the destructive nature of BDD anodes they can be exploited for chemical synthesis.
<i>meso</i>-Tetraphenylporphyrin Iron Chloride Catalyzed Selective Oxidative Cross-Coupling of Phenols
作者:Hadas Shalit、Anna Libman、Doron Pappo
DOI:10.1021/jacs.7b05898
日期:2017.9.27
A novel catalytic system for oxidative cross-coupling of readily oxidized phenols with poor nucleophilic phenolic partners based on an iron meso-tetraphenylporphyrin chloride (Fe[TPP]Cl) complex in 1,1,1,3,3,3-hexafluoropropan-2-ol (HFIP) was developed. The unique chemoselectivity of this reaction is attributed to the coupling between a liberated phenoxyl radical with an iron-ligated phenolic coupling
An iron-catalyzed oxidative unsymmetrical biphenol coupling in 1,1,1,3,3,3-hexafluoropropan-2-ol that proceeds via a chelated radical anion coupling mechanism was developed. Based on mechanistic studies, electrochemical methods, and density functional theory calculations, we suggest a general model that enables prediction of the feasibility of cross-coupling for a given pair of phenols.