Selective synthesis of ureas and tetrazoles from amides controlled by experimental conditions using conventional and microwave irradiation

An efficient synthetic procedure has been achieved for selective synthesis of 1,5-disubstituted tetrazoles and diaryl ureas from secondary amides in situ in the presence of NaN3 and POCl3 as solvent, both by conventional and microwave methods. The reaction conditions were optimized to yield selectively either tetrazoles or urea derivatives from reasonable to excellent yields. These conversions have been tested and verified with various secondary amide precursors. The synthesized compounds were characterized by 1H NMR, 13C NMR and ESI-MS spectroscopic techniques.