Basic Ionic Liquid [DPPA] Cl⁻ Catalyzed Synthesis of Fluorescent 3‐ Acetoacetyl −6‐ aryldiazenyl‐ coumarins

Abstract

An efficient basic ionic liquid 1‐[3‐(dimethylamino)propyl]‐2,3,4,6,7,8,9,10‐octahydro‐1H‐pyrimido[1,2‐a]azepin‐5‐ium chloride, [DPPA] Cl− is designed for the convenient synthesis of diversely functionalized 3‐ acetoacetyl −6‐ aryldiazenyl‐ coumarins from 5‐aryldiazenyl salicylaldehydes and 4‐hydroxy‐6‐methyl‐2‐pyrone in ethanol‐water mixed solvent system. The synergic effect of DBU nucleus and tethered basic dimethylaminopropyl chain facilitates efficient catalysis of the reaction. Novelty of method is synthesis of highly conjugated molecular scaffold with the assistance of hybrid reusable basic ionic liquid, atom economy, wide substrate scope, short reaction time, high yields and use of eco‐benign ethanol‐water mixed solvent system, etc. The synthesized compounds exhibit fluorescence properties that could unlock the window for their use as a fluorescent material.

Docking Study, Synthesis, and Anti-Inflammatory Potential of Some New Pyridopyrimidine-Derived Compounds

“…45 On the other hand, phenyldiazenyl aldehydes IIa-i were achieved through diazotization of various anilines followed by treatment with aromatic aldehydes under basic conditions. [46][47][48] The synthesis of the target pyridopyrimidinones IIIa-i was accomplished in 66-93% yield by treatment of compound I with various phenyldiazenyl aromatic aldehydes in CH 3 OH containing a catalytic amount of HCl adopting the reported method. 34 In this reaction, the acidic polar solvent favors the reaction progress by the creation of a 6-imino that directs to higher nucleophilic character of carbon five, causing reaction to occur on the aromatic aldehydic carbonyl (Scheme 2).…”

Glucose Isomerizes to Fructose Catalyzed by the Eco‐Friendly and Biodegradable Ionic Liquids

“…These ILs are comprised of a choline cation and different natural amino acid anions (Scheme ). As organic ionic salts formed from the cheap starting materials, these catalysts have all advantages of the conventional ILs, for example, high catalytic activity because of its uniform catalytic active center, facile separation from the reaction system, and good reusability . Particularly, these ILs are more biodegradable, non‐toxic and cost‐effective in comparison with the conventional imidazolium and pyridinium salts .…”