Synthesis of Sulfonamide-Based Ynamides and Ynamines in Water
作者:Lei Zhao、Hongyi Yang、Ruikun Li、Ye Tao、Xiao-Feng Guo、Edward A. Anderson、Andrew Whiting、Na Wu
DOI:10.1021/acs.joc.0c02326
日期:2021.1.15
Ynamides, though relatively more stable than ynamines, are still moisture-sensitive and prone to hydration especially under acidic and heating conditions. Here we report an environmentally benign, robust protocol to synthesize sulfonamide-based ynamides and arylynamines via Sonogashira coupling reactions in water, using a readily available quaternary ammonium salt as the surfactant.
Negishi coupling of terminal alkynyl amides with (hetero)aryl iodides in the presence of Pd2dba3 and triphenylphosphine affords new alkynyl amides in yields of up to 90%.
Coupling and cycloaddition of ynamides: homo- and Negishi coupling of tosylynamides and intramolecular [4+2] cycloaddition of N-(o-ethynyl)phenyl ynamides and arylynamides
tosylamides derivatives with (hetero)aryl iodides in the presence of Pd2dba3 and triphenylphosphine affords N-aryl and N-alkyl arylynamides in yields of up to 90%. Intramolecular [4+2] cycloaddition reactions of N-ethynylphenyl ynamides and arylynamides allow the synthesis of carbazoles and benzannulated and heteroannulated carbazoles in moderate-to-good yields.