H_(4)SiW_(12)O_(40)-catalyzed cyclization of epoxides/aldehydes and sulfonyl hydrazides: An efficient synthesis of 3,4-disubstituted 1H-pyrazoles  

作　　者：Guoping Yang Xuanjie Xie Mengyuan Cheng Xiaofei Gao Xiaoling Lin Ke Li Yuanyuan Cheng Yufeng Liu 

机构地区：[1]Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation,Jiangxi Province Key Laboratory of Synthetic Chemistry,East China University of Technology,Nanchang 330013,China [2]Henan Key Laboratory of Polyoxometalate Chemistry,College of Chemistry and Chemical Engineering,Henan University,Kaifeng 475004,China

出　　处：《Chinese Chemical Letters》2022年第3期1483-1487,共5页中国化学快报（英文版）

基　　金：financially supported by the National Natural Science Foundation of China (Nos. 22001034 and 21804019);the Open Fund of the Jiangxi Province Key Laboratory of Synthetic Chemistry (No. JXSC202008);the Research Found of East China University of Technology (Nos. DHBK2019264, DHBK2019265 and DHBK2019267)。

摘　　要：A simple and efficient method for the synthesis of pyrazoles through a silicotungstic acid (H_(4)SiW_(12)O_(40))-catalyzed cyclization of epoxides/aldehydes and sulfonyl hydrazides has been developed. Various epoxides/aldehydes were smoothly reacted with sulfonyl hydrazides to furnish regioselectivity 3,4-disubstituted 1H-pyrazoles. The application of such an earth-abundant, readily accessible, and nontoxic catalyst provides a green approach for the construction of 3,4-disubstituted 1H-pyrazoles. A plausible reaction mechanism has been proposed on the basis of control experiments, GC-MS and DFT calculations.

关 键 词：Silicotungstic acid EPOXIDES ALDEHYDES Sulfonyl hydrazides 3 4-Disubstituted 1H-pyrazoles 

分 类 号：O626[理学—有机化学]