The Au(III)-catalyzed cyclization of 2-alkynylanilines was combined in a one-pot procedure with the Au(I)-catalyzed C3-selective direct alkynylation of indoles using the benziodoxolone reagent TIPS-EBX to give a mild, easy and straightforward entry to 2-substituted-3-alkynylindoles. The reaction can be applied to unprotected anilines, was tolerant to functional groups and easy to carry out (RT, and requires neither an inert atmosphere nor special solvents).
Brand, J. P., Chevalley, C., & Waser, J. (2011). One-pot gold-catalyzed synthesis of 3-silylethynyl indoles from unprotected o-alkynylanilines. Beilstein Journal of Organic Chemistry, 7, 565–569. https://doi.org/10.3762/bjoc.7.65