Synthesis of Substituted Quinolines by the Electrophilic Cyclization of N-(2-Alkynyl)anilines
Xiaoxia Zhang1, Tuanli Yao, Marino A Campo
1Department of Chemistry, Iowa State University, Ames, Iowa 50011.
Abstract:
A wide variety of substituted quinolines are readily synthesized under mild reaction conditions by the 6-endo-dig electrophilic cyclization of N-(2-alkynyl)anilines by ICl, I(2), Br(2), PhSeBr and p-O(2)NC(6)H(4)SCl. The reaction affords 3-halogen-, selenium- and sulfur-containing quinolines in moderate to good yields in the presence of various functional groups. Analogous quinolines bearing a hydrogen in the 3-position have been synthesized by the Hg(OTf)(2)-catalyzed ring closure of these same alkynylanilines.
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