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.
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
Organocatalytic Enantioselective Synthesis of Chiral Allenes: Remote Asymmetric 1,8‐Addition of Indole Imine Methides
作者:Xingguang Li、Jianwei Sun
DOI:10.1002/anie.202006137
日期:2020.9.21
synthesis of chiral tetrasubstituted allenes is disclosed. With suitable chiral phosphoric acid catalysts, a range of racemic indole‐substituted propargylic alcohols reacted with nucleophiles to provide efficient access to a series of enantioenriched allenes with high enantioselectivities. Control experiments suggested a mechanism involving remotely controlled asymmetric 1,8‐addition of the in situ
A novel palladium‐catalyzed approach to direct C‐3‐arylation of 1H‐indoles with arylhydrazines using air as the oxidant viaCN bond cleavage has been developed. Various substituents are tolerated in this system in moderate to good yields. This reaction could also be compatible with a larger scale. Thus, this strategy using arylhydrazines as arylating reagents provides a powerful method for constructing
Construction of Axially Chiral Styrenes Linking an Indole Moiety by Chiral Phosphoric Acid
作者:Wenxuan Zhang、Ran Song、Daoshan Yang、Jian Lv
DOI:10.1021/acs.joc.1c02750
日期:2022.3.4
intermolecular C2 Friedel–Crafts alkylation reaction between ortho-alkynylnaphthols and various 3-substitutedindoles, affording axially chiral alkenes with up to 93% yields (E/Z > 20:1) and up to 98% ee under mild reaction condition. Other substituted indole derivatives could be also tolerated in this system, giving the corresponding axially chiral alkenes with high yields and in excellent enantioselectivity