A mild and efficient method for halogenation of 3,5-dimethyl pyrazoles by ultrasound irradiation using N-halosuccinimides
作者:Hélio A. Stefani、Claudio M.P. Pereira、Roberta B. Almeida、Rodolpho C. Braga、Karla P. Guzen、Rodrigo Cella
DOI:10.1016/j.tetlet.2005.08.027
日期:2005.10
The 4-halo-3,5-dimethyl pyrazoles have been synthetisized in good yields in short reaction times in the absence of a catalyst by reaction of 3,5-dimethyl pyrazoles with N-halosuccinimides (NBS, NCS and NIS) under ultrasound irradiation. Finally, the halogenation of pyrazoles with Br2, ICl and I2 was showed in similar conditions.
在无催化剂的情况下,通过3,5-二甲基吡唑与N-卤代琥珀酰亚胺(NBS,NCS和NIS)在超声辐射下的反应,可以在较短的反应时间内以较短的反应时间合成4-卤代3,5-二甲基吡唑。。最后,在相似的条件下显示出用Br 2,ICl和I 2卤化吡唑。