On the interaction of Lewis acids on pyrroles and indoles

Although the ability of Lewis acids to initiate oligomerisation or polymerisation of pyrroles and indoles is known, no reliable information was available on the structures of the complexes formed therewith. Using 1H NMR spectroscopy, an attempt has now been made to elucidate the structures of the complexes formed by the treatment of pyrroles and indoles with AlCl3.