A Simple One-Pot Synthesis of 2-Substituted Quinazolin-4(3H)-ones from 2-Nitrobenzamides by Using Sodium Dithionite

A simple one-pot procedure for the preparation of 2-(het)arylquinazolin-4(3H)-ones starting from readily available 2-nitrobenzamides and (het)aryl aldehydes is described. Sodium dithionite is used as the reducing agent for the nitro group, and its decomposition in situ in aqueous N,N-dimethylformamide leads to the final oxidation step that gives the desired heterocyclic compounds.