LiClO4/EG as an Environmentally Benign Lewis Acidic Catalytic System for the Expeditious Synthesis of 2,3-Dihydroquinazolin-4 (1H)-ones and NH-1,2,3-Triazoles

An environmentally benign protocol has been developed for the synthesis of two biologically important N-heterocycles; namely, 2,3-dihydroquinazolin-4(1H)-ones and NH-1,2,3-triazoles. These two N-heterocyclic systems are synthesized using readily available and inexpensive LiClO4 in ethylene glycol (EG) and PEG-400 with good to excellent product yield. The method provides an important benchmark for the rapid, operationally simple synthesis of these two heterocycles. Sc-XRD analysis of one of the products gives structural information and DFT calculations provide important information on the mechanistic pathway.