An efficient synthesis of quinazoline-2,4-dione derivatives with the aid of a low-valent titanium reagent

A facile synthetic method using low-valent titanium reagent (TiCl4/Zn system) to promote the novel reductive cyclization of 2-nitrobenzamides and triphosgene is described. Sequentially, a series of quinazoline-2,4-diones were synthesized in good yields. (c) 2007 Elsevier Ltd. All rights reserved.