A highly regioselective hydroamination of unsymmetricalelectron-poor and electron-richalkynes with anilinescatalyzed by Au(I) under mild conditions is reported. In addition, applications toward indole syntheses are presented including an example of a one-pot synthesis from a nonfunctionalized aniline.
Starting from simple anilines and ester arylpropiolates, an efficient one-pot synthesis of 2-arylindole-3-carboxylate derivatives has been developed through copper-mediated sequential hydroamination and cross-dehydrogenative coupling (CDC) reaction. The initial hydroamination of anilines to ester arylpropiolates in benzene can proceed in a stereoselective manner to give ester (Z)-3-(arylamino)acrylates
arylnitrones and diazo compounds by C–H activation/[4 + 1] annulation with a C(N2)–C(acyl) bond cleavage is reported, and 2,3-disubstituted NH indoles are directly synthesized in up to a 94% yield. A variety of functional groups are applicable to this reaction to give the corresponding products with high selectivity. Compared to other previously reported Rh(III)-catalyzed synthesis of homologous series, this method
Synthesis of Unprotected and Highly Substituted Indoles by the Ruthenium(II)-Catalyzed Reaction of Phenyl Isocyanates with Diaryl/Diheteroaryl Alkynes/Ethyl-3-phenyl Propiolates
作者:Amrendra Kumar、Narender Tadigoppula
DOI:10.1021/acs.orglett.0c02793
日期:2021.1.1
unprotected and highly substituted indoles by an in situ installed carbamide-directed Ru(II)-catalyzed intermolecular oxidative annulation of phenyl isocyanates with diaryl/diheteroaryl alkynes/ethyl phenyl propiolates in the presence of Cu(OAc)2·H2O as an oxidant and AgSbF6 as an additive at 120 °C within 3 h.
I2-Catalyzed Indole Formation via Oxidative Cyclization of N-Aryl Enamines
作者:Zhiheng He、Weiping Liu、Zhiping Li
DOI:10.1002/asia.201100045
日期:2011.6.6
Cat.′s Is: An I2‐catalyzed synthesis of indoles, taking advantage of intramolecular dehydrogenative coupling reactions of enamines, afforded a variety of multifunctionalized indole derivatives in good to excellent yields under transition‐metal‐free reaction conditions.