Facile synthesis of pyrazoles by iron-catalyzed regioselective cyclization of hydrazone and 1,2-diol under ligand-free conditions
作者:Niranjan Panda、Subhadra Ojha
DOI:10.1016/j.jorganchem.2018.02.043
日期:2018.4
A facile synthesis of pyrazoles by the cyclization of hydrazones and 1,2-diols was described. In the presence of ferric nitrate, the reaction occurs under neat conditions and makes the use of potassium persulfate to oxidize the diol to α-hydroxy carbaldehyde for the reaction with hydrazones to produce 1,3- and 1,3,5-substituted pyrazoles selectively. The overall regioselective transformation occurs
描述了通过和1,2-二醇的环化容易地合成吡唑。在硝酸铁存在下,反应在纯净条件下发生,并利用过硫酸钾将二醇氧化为α-羟基甲醛,与反应生成选择性生成1,3-和1,3,5-取代的吡唑。整体区域选择性转化在无配体的温和条件下甚至在空气中一锅进行。