Phenyliodonium Diacetate Mediated One-Pot Synthesis of Benzimidazoles and Quinazolinones from Benzylamines

An efficient metal-free, one-pot protocol was developed for the synthesis of variety benzimidazole and quinazolinones in moderate to good yields. This protocol proceeds via oxidation of benzylamine, resulting in in-situ aldehyde formation followed by the condensation with o-phenylenediamine and o-amino-benzamide to the corresponding N-heterocycles using a mild oxidant phenyliodonium diacetate (PIDA). We describe a new strategy for C-N bond cleavage and formation in the absence of transition-metal reagent or ligand under environmentally benign reaction conditions.