Highly Regioselective One-Pot, Three-Component Synthesis of 1-Aryl-3,4-Substituted/Annulated-5-(Cycloamino)/(Alkylamino)pyrazoles from β-Oxodithioesters
作者:Ganesh C. Nandi、Maya S. Singh、Hiriyakkanavar Ila、Hiriyakkanavar Junjappa
DOI:10.1002/ejoc.201101397
日期:2012.2
An efficient, highly regioselective protocol for the synthesis of the title compounds is reported. The reaction involves a one-pot, three-component cyclocondensation of β-oxodithioester, amine, and hydrazine in ethanol at reflux in the presence of a catalytic amount of acetic acid. Densely functionalized pyrazoles were constructed through the cyclization of a thioamide intermediate generated in situ
报告了一种用于合成标题化合物的高效、高度区域选择性的方案。该反应包括β-氧代二硫酯、胺和肼在乙醇中在催化量的乙酸存在下回流的一锅三组分环缩合反应。通过环化由 β-氧代二硫酯原位生成的硫代酰胺中间体,构建了密集功能化的吡唑。这种方法可以快速和通用地合成以前无法获得的吡唑和合成要求高的含有稠环的吡唑。