{"title":"A highly efficient and green method for catalyzing the Hantzsch reaction under solvent-free conditions using a seashell/Kaolin calcined system","authors":"Mohamed-Zakaria Stiti, Tahir Habila, Ammar Khaled, Mourad Bouhedja, Jean-Jacques Pireaux, Smail Khelili","doi":"10.1007/s12039-023-02190-1","DOIUrl":null,"url":null,"abstract":"<div><p>A green method for synthesizing 1,4-dihydropyridines (<b>1a-j</b>) by a one-pot reaction of various aldehydes, ethyl acetoacetate, and ammonium carbonate, catalyzed by a seashell and kaolin powders, mixed and calcined at 500 and 800 °C, under solvent-free conditions, has been developed. The catalyst was characterized by physicochemical techniques, namely, X-ray diffraction (XRD), electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). The mixture composed of 20% seashell and 80% Kaolin (Q3-500), calcined at 500 °C, gave the best results (78 to 96% yields). Q3-500 separation from the reacting medium was carried out by filtration and reused several times with a slight decrease in yields. Compared with other conventional methods, the present method is inexpensive and offers advantages, namely: the catalyst is eco-friendly, recyclable, and gives high yields with shorter reaction time.</p><h3>Graphical Abstract</h3><p>A seashell/Kaolin calcined system (20/80) at 500°C was elaborated to catalyze the Hantzsch reaction under solvent-free conditions. Using Q3-500 six times gave dihydropyridines with excellent yields with a slight loss of activity. The improvement of the catalytic properties of the kaolin surface is due to the increase of cationic content.</p>\n <figure><div><div><div><picture><source><img></source></picture></div></div></div></figure>\n </div>","PeriodicalId":50242,"journal":{"name":"Journal of Chemical Sciences","volume":null,"pages":null},"PeriodicalIF":1.7000,"publicationDate":"2023-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s12039-023-02190-1.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Chemical Sciences","FirstCategoryId":"92","ListUrlMain":"https://link.springer.com/article/10.1007/s12039-023-02190-1","RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"Chemistry","Score":null,"Total":0}
引用次数: 0
Abstract
A green method for synthesizing 1,4-dihydropyridines (1a-j) by a one-pot reaction of various aldehydes, ethyl acetoacetate, and ammonium carbonate, catalyzed by a seashell and kaolin powders, mixed and calcined at 500 and 800 °C, under solvent-free conditions, has been developed. The catalyst was characterized by physicochemical techniques, namely, X-ray diffraction (XRD), electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). The mixture composed of 20% seashell and 80% Kaolin (Q3-500), calcined at 500 °C, gave the best results (78 to 96% yields). Q3-500 separation from the reacting medium was carried out by filtration and reused several times with a slight decrease in yields. Compared with other conventional methods, the present method is inexpensive and offers advantages, namely: the catalyst is eco-friendly, recyclable, and gives high yields with shorter reaction time.
Graphical Abstract
A seashell/Kaolin calcined system (20/80) at 500°C was elaborated to catalyze the Hantzsch reaction under solvent-free conditions. Using Q3-500 six times gave dihydropyridines with excellent yields with a slight loss of activity. The improvement of the catalytic properties of the kaolin surface is due to the increase of cationic content.
期刊介绍:
Journal of Chemical Sciences is a monthly journal published by the Indian Academy of Sciences. It formed part of the original Proceedings of the Indian Academy of Sciences – Part A, started by the Nobel Laureate Prof C V Raman in 1934, that was split in 1978 into three separate journals. It was renamed as Journal of Chemical Sciences in 2004. The journal publishes original research articles and rapid communications, covering all areas of chemical sciences. A significant feature of the journal is its special issues, brought out from time to time, devoted to conference symposia/proceedings in frontier areas of the subject, held not only in India but also in other countries.