Synthesis of N-Substituted Indole Derivatives via PIFA-Mediated Intramolecular Cyclization
作者:Yunfei Du、Renhe Liu、Gregory Linn、Kang Zhao
DOI:10.1021/ol062288o
日期:2006.12.1
A variety of N- arylated and N- alkylated indole derivatives were synthesized by way of a phenyliodine bis( trifluoroacetate) ( PIFA)- mediated intramolecular cyclization. This novel method allows for the construction of an indole skeleton by joining the N- atom on the side chain to the benzene ring at the last synthetic step. Other novel pyrrole- fused aromatic compounds can also be achieved by this method.
Oxidative Cyclization of 2-Aryl-3-arylamino-2-alkenenitriles to <i>N</i>-Arylindole-3-carbonitriles Mediated by NXS/Zn(OAc)<sub>2</sub>
N-arylindole-3-carbonitriles in a one-pot manner through NBS- or NCS-mediated halogenation followed by Zn(OAc)2-catalyzed intramolecular cyclization. It is postulated that the process involves the formation of arylnitrenium ionintermediates, which undergo the electrophilic aromaticsubstitution to give the cyclized N-arylindole product.