PPh3-Catalyzed Intramolecular Cyclization of hydroxypropargylamides: Synthesis of Structurally Diverse Morpholinone Derivatives

Abstract

The metal-free synthesis of functionalized morpholinones through a sequential intramolecular post-ugi cyclization strategy is described. In the subsequent step, Ugi adducts hydroxypropargylamides derivative undergoes chemo- and regioselective 6-exo-dig catalytic cyclization to afford O-cyclized product in the presence of triphenylphosphine. This sequence offers an engrossing functionalized morpholinones scaffolds involving moderate reaction conditions with broad substrate scopes and moderate to good yields.