A short and efficient access to benzo[c]phenanthridines and phenanthridinones is achieved by the action of phenyliodine(III)-bis(trifluoroacetate) (PIFA) on properly substituted benzylnaphthylamines and naphthylbenzamides, respectively. This reagent promotes a non-phenolic oxidative biaryl coupling process, the key step of the synthesis. A study of the electronic and steric requirements of the substrates
通过苯碘(III)-双(三氟乙酸)酯(PIFA)分别作用于适当取代的苄基萘胺和萘并苯甲酰胺上,可以短而有效地获得苯并[ c ]菲啶和菲啶酮。该试剂促进了非酚氧化联芳基的偶联过程,这是合成的关键步骤。由于在某些情况下,二聚化过程优于分子内环化作用,因此需要对底物的电子和空间要求进行研究。机械建议也包括在内。
Catalyst-Free Singlet Oxygen-Promoted Decarboxylative Amidation of α-Keto Acids with Free Amines
catalyst-free decarboxylative amidation of α-ketoacids with aminesundermildconditions has been developed. Advantages of the new protocol include avoidance of metal catalysts and high levels of functional group tolerance. In addition, the reaction can be scaled up and shows high chemoselectivity. Preliminary mechanistic studies suggest that singlet oxygen, generated from oxygen under irradiation, is the key
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
Copper-catalyzed synthesis of arylcarboxamides from aldehydes and isocyanides: the isocyano group as an N1 synthon
作者:Jian-Quan Liu、Xuanyu Shen、Zhenhua Liu、Xiang-Shan Wang
DOI:10.1039/c7ob01449j
日期:——
An interesting radical coupling reaction of aromatic aldehydes with isocyanides was disclosed for the synthesis of amides catalyzed by copper. According to the experimental results and mechanistic study, the isocyano group acted as an N1 synthon rather than exhibiting the carbene-like reactivity, exploiting a new reactivityprofile of isocyanides.
Synthesis of polysubstituted 1,2-dihydroquinolines and indoles via cascade reactions of arylamines and propargylic alcohols catalyzed by FeCl<sub>3</sub>·6H<sub>2</sub>O
作者:Min Shao、Yunjun Wu、Zhijun Feng、Xiaoxia Gu、Shaoyin Wang
DOI:10.1039/c5ob02658j
日期:——
friendly and high-yielding route from inexpensive starting materials to 1,2-dihydroquinolines has been developed. This procedure proceeded via a cascade Friedel–Crafts-type reaction and 6-endo-trig hydroamination under the catalysis of FeCl3·6H2O, involving the formation of two new σ (C–C and C–N) bonds in a single operation for the construction of a 1,2-dihydroquinoline skeleton in good to excellent yields