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
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.
constructed from indoles and cyclohexanone derivatives using a combination of catalytic niobic acid-on-carbon (Nb2O5/C) and palladium-on-carbon (Pd/C) under heating conditions without any oxidants. The Lewis acidic Nb2O5/C promoted the nucleophilic addition of indoles to the cyclohexanones, and the subsequent dehydration and Pd/C-catalyzed dehydrogenation produced the 3-arylindoles. The additive 2
A two‐step synthesis of structurally diverse pyrrole‐containingbicyclic systems is reported. ortho‐Nitro‐haloarenes coupled with vinylic N‐methyliminodiacetic acid (MIDA) boronates generate ortho‐vinyl‐nitroarenes, which undergo a “metal‐free” nitrene insertion, resulting in a new pyrrole ring. This novel synthetic approach has a wide substrate tolerance and it is applicable in the preparation of
Palladium-Catalyzed Direct Arylation of Indoles with Cyclohexanones
作者:Shanping Chen、Yunfeng Liao、Feng Zhao、Hongrui Qi、Saiwen Liu、Guo-Jun Deng
DOI:10.1021/ol500231c
日期:2014.3.21
A novel palladium catalyzed approach to 3-arylindoles was developed from indoles and cyclohexanones. Various cyclohexanones acted as aryl sources via an alkylation and dehydrogenation sequence using molecular oxygen as the hydrogen acceptor. This method showed good regioselectivity and afforded 3-arylindoles as the sole products.