WebJun 1, 2006 · Synthesis Coumarin derivatives were prepared using zirconyl chloride octahydrate (1%) as a Pechmann catalyst, either neat or in some cases employing small volumes of ethanol as solvent. As result of this work, coumarins were obtained in moderate to good yields. View via Publisher Save to Library Create Alert Cite Tables from this paper … WebSep 15, 2010 · The preparation of pyrazole derivatives involving a 1,3-dipolar cycloaddition between a diazomethane (or other diazonium salt) and a molecule with carbon-carbon …
Mechanochemical synthesis of coumarins via Pechmann …
WebFeb 25, 2011 · Synthesis of coumarins A mixture of substituted phenol (1 mmol) and β-ketoester (1 mmol) was ground with dry p -TSA (2 mmol) in a mortar by pestle for 10 minutes when a color change of the reaction mixture took place. The reaction mixture was kept at room temperature for about 20–80 minutes. WebMay 15, 2005 · The Pechmann reaction introduces one of the most significant and simple methods for the synthesis of a variety of heterocyclic compounds, particularly coumarin derivatives. In 1883, a German chemist, Hans von Pechmann synthesized coumarins from the reaction of phenols with a carboxylic acid or ester containing a β -carbonyl group. inloggen cosis webmail
Overview on developed synthesis procedures of coumarin
WebAug 17, 2012 · In summary, the presented report demonstrates facile barium dichloride-catalyzed synthesis of coumarins via the Pechmann reactions. The important advantages of this method are the short reaction time, high yields, simple workup, the use of inexpensive and available catalyst, the nonchromatographic purification of products, that is, simple … WebMay 1, 2002 · Synthesis of a NbO Type Homochiral Cu(II) Metal–Organic Framework: Ferroelectric Behavior and Heterogeneous Catalysis of Three-Component Coupling and Pechmann Reactions. Inorganic Chemistry 2024 , 56 (8) , 4697-4705. WebJan 25, 2024 · A green protocol has been developed for the synthesis of simple coumarins and linear pyrano[2,3-f] and [3,2-f]indoles by the reaction of phenol derivatives with β-ketoesters under ball milling at ambient temperature in the presence of methanesulfonic acid as a mild acid catalyst.The significant advantages of this procedure are high yields, … mockup cover book arabic