取代查耳酮肟电化学氧化机理的研究

研究了７种取代查耳酮肟的电化学行为。用氢氧化钠底液热解石墨工作电极，取代查耳酮肟的电极过程为１ｅ氧化不可逆吸附电极过程。它们的氧化电位随取代基吸电子能力的增强而增高，并与它们相应的Ｈａｍｍｅｔｔ常数呈线性关系。取代查耳酮肟的电化学氧化机理为先失去一个电子生成ｉｍｉｎｏｘｙ自由基，然后由基对分子内烯键进行环化加成，脱氢后形成３，５－二聚代异恶唑。用控电位电解和紫外吸收光谱检测了部份电化学氧化产物，证

Study on the Electrochemical Oxidation of Substituted Chalcone Oximes

The electrochemical oxidation of 7 substituted chalcone oximes was studied. The results show that the chalcone oximes are first oxidized to iminoxy radicals and then transformed via cycloaddition to the 3,5-diarylisoxazoles, it appears to be an irreversible reaction and adsorptive process at lower potential sweep rate. The products of electrochemical oxidation of chalcones oximes have been, confirmed by controlled potential electrolysis and UV-spectrophotometry. For monosubstituted chalcone oximes there exists a linear relationship between the oxidative potentials and the Hammett constants of the substituents. The oxida-tive potential increases with increasing electrowithdrawing power of the substituent. The electrochemical oxidation can be used for generating 3, 5-diarylisoxazoles from substituted chalcone oximes.