A new entry to the preparation of pyrrolo[2,3-b]quinolines by an aza Wittig/electrocyclic ring-closure/nitrene insertion process

Article abstract of DOI:10.1016/S0040-4020(97)00038-0

A new method for the preparation of the pyrrolo[2,3-b]quinoline ring system involving the sequential formation of the pyridine ring (elcctrocyclic ring-closure) and the pyrrole (nitrene insertion reaction) rings. This approach is based on the regioselective formation of the iminophosphorane 2 from the bis(azide) 1, followed by aza Wittig reaction with isocyanates and further thermal treatment.