Synthesis of 4,5-Dihydroisoxazoles from <i>N</i>-Nitroso-4,5-dihydropyrazoles under Microwave Activation
作者:Alexander Stepakov、Ivan Galkin、Rafael Kostikov、Galina Starova、Zoya Starikova、Alexander Molchanov
DOI:10.1055/s-2007-977455
日期:——
Substituted bicyclic and spirocyclic N-nitroso-4,5-dihydropyrazoles eliminate nitrogen under microwave irradiation within 3-8 minutes in solvent (chlorobenzene-DMF and chlorobenzene-AcOH) or in solvent-free conditions (on SiO2) to afford the corresponding 4,5-dihydroisoxazole derivatives. This methodology represents an improvement on thermolysis and allows 4,5-dihydroisoxazole systems to be obtained in good yields.
取代的双环和螺环 N-亚硝基-4,5-二氢吡唑在微波辐照下,在溶剂(氯苯-DMF 和氯苯-AcOH)或无溶剂条件(SiO2)下 3-8 分钟内脱氮,得到相应的 4,5-二氢异噁唑衍生物。这种方法是对热分解法的改进,能以良好的产率获得 4,5-二氢异噁唑体系。