ZnO: An Ecofriendly, Green Nano-catalyst for the Synthesis of Pyrazole Derivatives under Aqueous Media
作者:Yarabally R. Girish、Kothanahally S. Sharath Kumar、Heggadihalli S. Manasa、Sheena Shashikanth
DOI:10.1002/jccs.201400170
日期:2014.11
An efficient nano ZnO catalyzed green protocol for the synthesis of pyrazol derivatives by condensation of different substituted phenyl hydrazines/semicarbazide/thiosemicarbazide with 1,3‐diketone/ketoester at ambient temperature has been achieved. ZnO nanocatalyst was prepared by low temperature solution combustion method. From the Scherrer method the crystallite size of ZnO was estimated and found
12-Tungstophosphoric acid (H3PW12O40) is found to be an efficient and recyclable catalyst in promoting a chemo- and regioselective condensation of hydrazines/hydrazides, diamines, and primary amines with various 1,3-dicarbonyl compounds in pure water at room temperature to afford pyrazoles, diazepines, and enaminones/enamino esters, respectively, in high yields.
[Ce(<scp>l</scp>-Pro)<sub>2</sub>]<sub>2</sub> (Oxa) as a heterogeneous recyclable catalyst: synthesis of pyrazoles under mild reaction conditions
作者:Ramesh Katla、Rakhi Chowrasia、Padma S. Manjari、Caren D. G. da Silva、Beatriz F. dos Santos、Nelson L. C. Domingues
DOI:10.1039/c6nj01723a
日期:——
A highly efficient method for the synthesis of pyrazoles mediated by [Ce(l-Pro)2]2 (Oxa) as a heterogeneous catalyst.
一种由[Ce(l-Pro)2]2 (Oxa)作为非均相催化剂介导的吡唑合成的高效方法。
An environmentally benign and efficient synthesis of 4‐Selanylpyrazoles catalyzed by haloid salts in water
作者:Yingguo Fang、Junxing Wang、Yuhong Liu、Jie Yan
DOI:10.1002/aoc.4921
日期:2019.6
An environmentally benign procedure is developed for the preparation of 4‐selanylpyrazoles from pyrazoles and diselenides. Using haloid salts as catalysts and H2O2 as oxidant, this catalytic protocol is convenient in water at room temperature under open‐air condition, and is suitable for a wide variety of starting materials and provides a series of 4‐selanylpyrazoles in good yields. A plausible catalytic
开发了一种环境友好的程序,用于从吡唑和二硒化物制备4-硒基吡唑。使用卤素盐作为催化剂,H 2 O 2作为氧化剂,该催化方案在室温,露天条件下的水中非常方便,适用于多种起始原料,并提供了一系列产率高的4-硒基吡唑。推测可能的催化亲电取代机理。
Room-Temperature Synthesis of Pyrazoles, Diazepines, <font>β</font>-Enaminones, and <font>β</font>-Enamino Esters Using Silica-Supported Sulfuric Acid as a Reusable Catalyst Under Solvent-Free Conditions
highly efficient regio- and chemoselective condensation of hydrazines/hydrazides, diamines, and primary amines with various β-dicarbonyl compounds at room temperature to afford pyrazoles, diazepines, and β-enaminones/β-enaminoesters under solvent-free conditions within 5–15 min.