Synthesis of New Azines in Various Reaction Conditions and Investigation of their Cycloaddition Reaction
R. Ranjbar-Karimia,* and H. Loghmani-Khouzanib
aDepartment of Chemistry, Faculty of Science, Vali-e-Asr University, Rafsanjan, Islamic Republic of Iran, P.O. BOX 77176
bDepartment of Chemistry, Faculty of Science, University of Isfahan, Isfahan, Islamic Republic of Iran
A series of new azines were prepared by reaction of 2-ketoalkyl quinoline derivatives with 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 13C NMR, 1H NMR, UV and IR spectrum. The results revealed that all compounds exist mostly in the enaminone form. We attempted to obtain criss-cross or probably Diels-Alder cycloaddition products through the reaction of some of these new azines with 2-chloroacrylonitrile as a dienophile. Some new diene systems developed from the said reactions.
Keywords: 2-Ketoalkyl quinoline, Azine, Tautomer, Criss-cross cycloaddition, Diels-Alder cycloaddition, Dienophile