A regioselective Csp2–H dual functionalization of indoles, which underlies bromo-amination via the 1,3-migration of imide groups on indolyl(phenyl)iodonium imides, has been developed to provide 2-bis(sulfonyl)amino-3-bromo-indoles under the metal-free conditions.
The Hofmann-type rearrangement of aromatic and aliphatic imides using KBr as the catalyst proceeded to provide aromatic and aliphatic amino acid derivatives. We have also developed a new synthetic route to gabapentin with this method.