Copper-Catalyzed Indole-Selective C-N Coupling Reaction of Indolyl(2-alkoxy-phenyl)iodonium Imides: Effect of Substituent on Iodoarene as Dummy Ligand.

A monoalkoxy phenyl group as a dummy ligand on indolyl(aryl)iodonium imides, which is related to the N-I bonding hypervalent iodine(III) compound, for the copper-catalyzed indole-selective C-N coupling reaction was designed to provide 3-bissulfonimido-indole derivatives in high yields. In particular, the use of indolyl(2-butoxylphenyl)iodonium bissulfonimides indicated the high indole selectivity. Furthermore, this reaction was applied for the one-pot synthesis of 3-bissulfonimido-indole derivatives directly from indoles with bissulfonimides and (diacetoxyiodo)-2-butoxybenzene in the presence of Cu(MeCN)4BF4 catalyst.