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
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.
“On Water” Direct and Site-Selective Pd-Catalysed CH Arylation of (NH)-Indoles
作者:Lionel Joucla、Nelly Batail、Laurent Djakovitch
DOI:10.1002/adsc.201000512
日期:2010.11.22
communication describes the development of a versatile catalytic system based on palladium(II) acetate/bis(diphenylphosphino)methane [Pd(OAc)2/dppm] that works “on water” giving site-selective CH arylation of (NH)-indoles without protecting or directing groups. Remarkably, the control of regioselectivity was achieved by small changes in the “extra-catalytic” base/halide partners. These innovative methodologies