Synthesis of some new 1-(6-fluorobenzothiazol-2-yl)-3-(4-fluoro- phenyl)-5-arylpyrazolines and their iodine(III) mediated oxidation to corresponding pyrazoles

摘要

The reaction of fluorinated chalcones 2 and 6-fluorobenzothiazol-2-ylhydrazine 1 in presence of catalytic amount of glacial acetic acid in refluxing ethanol yields 1-(6-fluorobenzothiazol-2-yl)-3-(4-fluorophenyl)-5-arylpyrazolines 3,which undergo facile oxidation to the corresponding pyrazoles 4 in good yield using iodobenzene diacetate (IBD).The structures of the synthesized compounds have been established on the basis of their elemental analysis,MS and 1H and 13C NMR spectroscopy.