Résumé
A facile route toward the synthesis of pentaleno(1,2-b) in-doles via multicomponent reaction of indole, aldehyde, and pentafulvene is realized. The reaction proceeds through Lewis acid catalyzed [3+2] cycloaddition of in situ generated indolylmethanol and pentafulvene. This methodology provides an easy access to biologically relevant indole derivatives.