A novel and facile carbodiimide-mediated synthesis of 2,3-dihydro-6 H-pyrimido[2,1- b]quinazolin-4(1 H)-ones via a tandem intramolecular nucleophilic addition/intramolecular hetero conjugate addition annulation strategy

Abstract

A novel and efficient carbodiimide-mediated synthetic method for new 2,3-dihydro-6 H-pyrimido[2,1- b]quinazolin-4(1 H)-ones ( 4) is described which involves initial intramolecular addition of an amino-nucleophile to the carbodiimide-cumulenic system, followed by intramolecular hetero conjugate addition annulation.