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

VICTORIA A. VAILLARD, MARÍA E. BUDÉN, SANDRA E. MARTÍN *, ROBERTO A. ROSSI

TETRAHEDRON LETTERS

Elsevier

Año: 2009 vol. 50 p. 3829 - 3832

0040-4039

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 SRN1 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 SRN1 reaction, the fused azaheterocycles were achieved (54–100%).