Synthesis of pyrrolo[3,2-α]phenazines from 5-nitroindoles and anilines

摘要

Anilines react with 5-nitroindoles in the presence of t-BuOK in N,N-dimethylformamide (DMF) to form 5-nitroso-4-arylaminoindoles that in turn when treated with N,O-bis(trimethylsilyl)acetamide cyclize to pyrrolo[3,2-α]phenazines. In an alternative approach pyr-rolo[3,2-α]phenazines are formed from aminoindoles and nitroarenes.