Synthesis of novel fused azaheterocycles by photostimulated intramolecular SRN1 reactions with nitrogen nucleophiles

The synthesis of pyrrole, indole, and pyrazole fused azaheterocycles is presented. The anions of carboxamides (6 and 12) and pyrazolylamines (15a-b) react under photostimulation by an intramolecular S_RN1 process to yield fused azaheterocycles with good to excellent yields. We report on an efficient two-step synthesis of new fused azaheterocycles derived from pyrrole, indole, and pyrazole, as well as the synthesis of their precursors. By the reaction of carboxamides (6 and 12) and pyrazolylamines (15a-b) with a base, the corresponding anion could be formed. Then, by an intramolecular photostimulated S_RN1 reaction, the fused azaheterocycles were achieved (54-100%).