some hydrazone in solvent free reaction conditions using ultrasonic irradiation. The
application of ultrasonic irradiation improved the yields and reduced the reaction times.
These azines, due to having α-acidic hydrogen next to azine group and heterocycle ring,
have tautomeric forms the degree of each of which was determined on the basis of 13 C
NMR, 1 H NMR, UV and IR spectrum. The results revealed that all compounds exist mostly …