One-pot synthesis of polyfunctional pyrazoles: an easy access to α-diazoketones from arylglyoxal monohydrates and tosylhydrazine
作者:Wen-Ming Shu、Jun-Rui Ma、Kai-Lu Zheng、Hui-Ying Sun、Mei Wang、Yan Yang、An-Xin Wu
DOI:10.1016/j.tet.2014.10.044
日期:2014.12
A new and efficient method for the generation of alpha-diazoketones has been developed from arylglyoxal monohydrates and tosylhydrazine at room temperature. 1,3-Dipolar cycloaddition reactions were used to constructing polyfunctional pyrazole derivatives by the reaction of generated alpha-diazoketones in situ with electron-deficient alkenes, quinones and coumarins in one pot. The one-dimensional molecular packing of 1H-benzo[f]indazole-4,9-dione derivatives along the c direction demonstrated a helical chain formation via N-H center dot center dot center dot O hydrogen-bonding. (C) 2014 Elsevier Ltd. All rights reserved.