Synthesis of cyclic ureas : Quinazolinediones and imidazolidinones from copper and DMAP-catalyzed reactions

Abstract

Quinazolinediones and imidazolidinones consisting of urea moiety displayed a wide range of biological activities. Quinazolinediones, hexacyclic urea, were synthesized from 2-iodobenzoic acids and carbodiimides via copper-catalyzed domino reactions. The domino processes include rearrangement of O-acylisourea and intramolecular C(aryl)-N bond formation. The electronic effect on aromatic ring of benzoic acid affected the product yields. A variety of quinazolinedione derivatives were synthesized in 22-80% yields. Imidazolidinones, pentacyclic urea, were synthesized from a-chloroaldoxime O-methanesulfonates and (E)-ethyl 4-(4- methoxyphenylamino)but-2-enoate via N,N-dimethylpyridin-4-amine (DMAP)-catalyzed reaction under mild conditions. The mechanism consisted of Tiemann rearrangement and intramolecular Michael addition to provide corresponding imidazolidinones in 4-65% yields.