Silica-supported 1,3-dichloro-5,5-dimethylhydantoin (DCH) as a useful reagent for microwave-assisted aromatization of 1,3,5-trisubstituted pyrazolines under solvent-free conditions
作者:Davood Azarifar、Elahe Nadimi、Mohammd Mehdi Ghanbari
DOI:10.1016/j.cclet.2010.10.023
日期:2011.4
1,3,5-Trisubstituted pyrazolines are rapidly and conveniently oxidized to their corresponding pyrazoles by 1,3-dichloro-5,5-dimethylhydantoin (DCH) in solution and solvent-free conditions under microwave irradiation. The presence of silica gel as a supporting agent is shown to be effective in reducing the reaction times and increasing the yields.
1,3,5-三取代的吡唑啉在微波辐射下,在无溶剂和无溶剂的条件下,被1,3-二氯-5,5-二甲基乙内酰脲(DCH)快速方便地氧化为相应的吡唑。硅胶作为支撑剂的存在被证明在减少反应时间和增加产率方面是有效的。