Gold-catalyzed intramolecular hydroamination of terminal alkynes in aqueous media: efficient and regioselective synthesis of indole-1-carboxamides
Deju Ye, Jinfang Wang, Xu Zhang, Yu Zhou, Xiao Ding, Enguang Feng, Haifeng Sun, Guannan Liu, Hualiang Jiang and Hong Liu
Green Chemistry. 2009, 11, 1201-1208
Using [Au(PPh3)]Cl/Ag2CO3-catalyzed 5-endo-dig cyclization in water under microwave
irradiation, we developed a fast and green route to prepare indole-1-carboxamides from
N¢-substituted N-(2-alkynylphenyl)ureas. The described method is tolerant to a variety of
functional groups, including N¢-aryl, alkyl, heterocyclic, various N-(substituted-2-ethynylphenyl)
and N-(2-ethynylpyridin-3-yl)ureas and affords moderate to high yields of the desired products.