A new synthetic method for triazatruxenes from indoles is developed using N-bromosuccinimide (NBS) as a user-friendly reagent. Major reaction parameters including the amount of NBS, substrate concentration, temperature, addition rate and addition method are investigated. Additional experiments are also conducted in order to gain access toward the reaction mechanism. Compared to the use of Br2 in the
Acid-Promoted Competing Pathways in the Oxidative Polymerization of 5,6-Dihydroxyindoles and Related Compounds: Straightforward Cyclotrimerization Routes to Diindolocarbazole Derivatives
indolylindoline 17 and the open trimer 18 can be isolated. Similar oxidation of the N-methyl (1b) and O,O-dimethyl (1c) derivatives of 1a, as well as of 5-methoxyindole (9b), 6-hydroxyindole (14a), and 6-benzyloxyindole (14b), afforded the corresponding diindolocarbazoles 5b and 6b, 5c and 6c, 10, 16, and the related tetramer 15 in up to 70% overall yield, whereas 5,6-diacetoxyindole (1d), 5-hydroxyindole (9a)