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a¹H NMR spectrum of β-CD in D2O at 70 °C temperature. b Magnified view of ¹H NMR spectrum of β-CD-salicylaldehyde inclusion complex at 70 °C
Source publication
Simple and green procedure was developed for the synthesis of various xanthene and coumarin derivatives using beta-cyclodextrin (β-CD) as reusable catalyst at 70 °C in water. Condensation of salicylaldehyde (1 mmol) and dimedone (2 mmol) or 1,3 cyclohexadione (2 mmol) gave corresponding xanthene derivatives, while condensation of salicylaldehyde (1...
Citations
A method for synthesizing xanthene and acridine derivatives using transition metal catalysts supported by de-alumination zeolite-NaY is described. Some transition metal ion-exchanged NaY zeolite was prepared and evaluated in a reaction toward the synthesis of xanthene and acridine. The most active catalyst in this field is a heterogeneous copper/zeolite catalyst. The synthesis of xanthene with a wide range of aldehydes/dimedone with a molar ratio of 1/2 and acridine synthesis with a molar ratio of dimedone/aromatic/ammonium nitrate of 2/1/1 was carried out in one pot and solvent-free conditions. Sensing in the presence of supported metal catalysts is operationally simple, does not require expensive or toxic reagents, and gives high yields in a short period.
In this review, we report β-cyclodextrin catalyzed green transformations of biologically active heterocycles. β-Cyclodextrin is a seminatural product, water-soluble, highly efficient, and biodegradable catalyst. β-Cyclodextrin is a versatile catalyst and promotes a variety of multi-component transformations, biomimetic reactions, C-C bond formation, and synthesis of some biologically active natural products. It has been applicable to attain some name reactions, deprotection of THP/MOM/Ac/Ts ethers, oxidative cleavage of epoxides, oxidative dehydrogenation of alcohol, regioselective cyclization of chalcone epoxides and 2’-aminochalcones. The catalyst is useful to carry out diastereoselective reactions, and it also plays a very important role in phase transfer catalysts.
In this research, two novel dicationic Brönsted acidic ionic liquids based on diethylamine were synthesized and characterized by various spectroscopic techniques such as Fourier transform infrared spectroscopy, Proton NMR (1H NMR), Carbon-13 NMR (13C NMR), Mass spectrometry as well as Hammett acidity function. The obtained results showed that the dicationic ionic liquid (DIL) to be efficient catalyst in the synthesis of 1, 8-dioxooctahydroxanthenes, 14-aryl-14H-dibenzo [a, j] xanthenes and 1, 8-dioxodecahydroacridines under solvent-free conditions. In addition, two DILs were investigated for their antibacterial activity against gram-positive and gram-negative bacterial strains by the agar diffusion method. Ease of preparation and handling of the catalyst, high yield of products in short reaction times, reusability of the catalyst, as well as high antibacterial activity of DILs are the main advantages of the present method.
