Synthesis of 3-Aminoquinazolinones via a SnCl₂-Mediated ANRORC-like Reductive Rearrangement of 1,3,4-Oxadiazoles

Herein, we developed a new SnCl₂-mediated ANRORC (addition of nucleophile, ring-opening, and ring-closure)-like rearrangement for the synthesis of 3-amino-2-substituted-quinazolin-4(3H)-one from 2-(2-nitrophenyl)-5-substituted-1,3,4-oxadiazole. The new method is solvent-dependent and features the use of a green solvent system (i.e., ethanol/water), high yields, and simple workup. The reduced product could be exclusively synthesized by changing the solvent to acetonitrile.