B(C6F5)(3)-catalyzed Markovnikov addition of indoles to aryl alkynes: an approach toward bis(indolyl)alkanes

The first example of the metal- and solvent-free B(C6F5)(3)-catalyzed Markovnikov addition of indoles to aryl alkynes was disclosed. Both N-H and N-protected indoles were tolerated, leading to a wide spectrum of versatile bis(indolyl)alkanes in moderate to good yields with high regioselectivities.