NHC-catalyzed regiodivergent syntheses of difunctionalized 3-pyrazolidinones from α-bromoenal and monosubstituted hydrazine
作者:Chenxia Yu、Shide Shen、Ligen Jiang、Jing Li、Yumiao Lu、Tuanjie Li、Changsheng Yao
DOI:10.1039/c7ob02041d
日期:——
A formal [3 + 2] annulation of α-bromoenal with monosubstituted hydrazine could give 1,5 or 2,5-difunctionalized 3-pyrazolidinone regiodivergently by tuning the structure of the N-Heterocyclic Carbene (NHC) catalyst.
A Convenient One-Pot Synthesis of 1-Aryl-Substituted 4-Iodopyrazol-3-Ols via Aromatisation and Oxidative Iodination Reactions
作者:Jingjing Liu、Shanguang Yang、Ruimei Dong、Zhudan Jin、Mingliang Wang
DOI:10.3184/174751918x15161933697808
日期:2018.1
A convenient and economical one-pot synthesis of a series of new 1-aryl-substituted 4-iodopyrazole-3-ols from easily available pyrazolidin-3-ones in the presence of sodium iodide, 30% solution of hydrogen peroxide and a catalytic amount of sulfuric acid in dichloromethane via aromatisation and oxidative iodination reactions are described. This protocol has the advantages of high atom economy, cost-effectiveness