Pd-free Sonogashira coupling: one pot synthesis of phthalide via domino Sonogashira coupling and 5-exo-dig cyclization

Abstract

Phthalides have been synthesized exclusively in one pot via Pd-free Sonogashira coupling. A Cu-catalyzed domino Sonogashira coupling and 5-exo-dig cyclization between suitable substituted ortho-bromobenzoic acids and terminal alkynes afforded phthalides in good yields under mild reaction conditions.