On the rearrangement of some Z-arylhydrazones of 3-benzoyl-5-phenylisoxazoles into 2-aryl-4-phenacyl-2H-1,2,3-triazoles: a kinetic study of the substituent effects in Boulton-Katritzky reactions

The rearrangement of eight new Z-arylhydrazones of 3-benzoyl-5-phenylisoxazoles (3d-k) into the relevant 2-aryl-4-phenacyl-2H-1,2,3-triazoles (4d-k) in dioxane/water solution at different proton concentrations has been quantitatively studied in a wide temperature range (293-333 K). The data collected together with some our previous ones on compounds 3a-c have allowed a deep study of the substituent effects on the course of the rearrangement, thus increasing our knowledge on the Boulton-Katritzky reactions in isoxazole derivatives and on the temperature effects on free energy relationships.

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