抽象的 吲哚支架的合成主要依靠N保护的链烯基苯胺的C–H氧化胺化作用进行C–N分子内环化反应。在此,在没有催化N的情况下,通过在催化量的FeF 2存在下使用K 2 S 2 O 8作为氧化剂,将各种容易制备的2-烯基苯胺以高收率转化成所需的吲哚产物。K 2 S 2 O 8 / FeF 2系统为3-芳基吲哚提供了直接而良性的合成途径,适用于包括药物中间体在内的各种取代的吲哚。 吲哚支架的合成主要依靠N保护的链烯基苯胺的C–H氧化胺化作用进行C–N分子内环化反应。在此,在没有催化N的情况下,通过在催化量的FeF 2存在下使用K 2 S 2 O 8作为氧化剂,将各种容易制备的2-烯基苯胺以高收率转化成所需的吲哚产物。K 2 S 2 O 8 / FeF 2系统为3-芳基吲哚提供了直接而良性的合成途径,适用于包括药物中间体在内的各种取代的吲哚。
The selective control over multiple competing C–H sites would enable straightforward access to functionalized indoles. In this context, we report here a modular and selective C–H arylation of indoles following the micellar catalysis approach using the third generation “designer” surfactant SPGS-550-M in the presence of 1 mol% of [(cinnamyl)PdCl]2 under mild conditions. Thus, access to high value C-arylated
Palladium−phenanthroline complexes efficiently catalyze the reaction of nitroarenes with arylalkynes and CO to give 3-arylindoles by an ortho-C−H functionalization of the nitroarene ring. Both electron-withdrawing and electron-donating substituents are tolerated on the nitroarene, except for bromide and activated chloride. Nitroarenes bearing electron-withdrawing substituents react faster, but the selectivity
Structure Ligation Relationship of Amino Acids for the Selective Indole C−H Arylation Reaction: L‐Aspartic acid as Sustainable Alternative of Phosphine Ligands
The S tructure L igation R elationship (SLR) of free amino acids (AAs) under Pd‐catalysis were examined for the chemo‐ and regio‐selective indole C−H arylation reactions. While the majority of AAs were minor or ineffective, the L‐aspartic acid (L‐Asp) stands out promising to deliver high‐value C3‐arylated indoles with excellent chemo‐ (C vs N) and regioselectivity (C3 vs C2) with high functional group
该小号tructure大号igation ř elationship(SLR)的游离氨基酸(AAS)下的Pd催化检查用于化疗和区域选择性的吲哚C-H芳基化反应。尽管大多数AA很少或无效,但是L-天冬氨酸(L-Asp)有望提供具有高化学(C vs N)和区域选择性(C3 vs C2)的高价值C3芳基吲哚功能组耐受性。因此,该方案为吲哚C3-H芳基化反应提供了基于膦的配体的经济高效且可持续的替代品。初步机械调查建议-NH的同时参与2,α-CO 2 H,和β-CO 2L‐Asp的H功能及其连接效率至关重要。所开发的催化系统与用于3芳基吲哚化学选择性合成的串联脱羧/芳基化程序兼容。
Palladium-catalyzed C-H formylation of electron-rich heteroarenes through radical dichloromethylation
作者:Yan Bao、Jian-Yong Wang、Ya-Xuan Zhang、Yan Li、Xi-Sheng Wang
DOI:10.1016/j.tetlet.2018.07.013
日期:2018.8
A novel palladium-catalyzed C-H formylation of electron-rich N-, O-, and S-containing heteroarenes has been developed. The key to success is that the commercially available BrCHCl2 was used as a stoichiometric carbonyl source. Mechanistic investigations indicated that different from the known Reimer-Tiemann reaction, this net C-H formylation proceeded through an electrophilc radical-type path.
Metal-free and regiospecific synthesis of 3-arylindoles
作者:Chuangchuang Xu、Wenlai Xie、Jiaxi Xu
DOI:10.1039/d0ob00317d
日期:——
arylhydrazine hydrochlorides and Fischer indolization. The organic base triethylamine plays a crucial role in the final elimination step in the Fischer indole synthesis, affording 3-arylindoles regiospecifically. The reaction features advantages of microwave acceleration, non-metal participation, short reaction time, organic acid-base co-catalysis, and broad substrate scope.