جستجوی مقالات مرتبط با کلیدواژه "green catalyst" در نشریات گروه "شیمی"

Imidazoles are the most important group of the nitrogen containing heterocyclic compounds and core of many of the biological systems which have a wide range of medicinal and biological properties. In the present research, for the first time, bis-phenanthroimidazole derivatives were synthesized via one-pot four-components reaction of aromatic aldehyde, 4,4’- diamino diphenyl ether, 9,10-phenanthrenequinone and ammonium acetate in the presence of lactic acid as catalyst. In order to investigate the effect of lactic acid as a catalyst in the synthesis of bis-phenantroimidazole derivatives and to find the optimal conditions, first one derivative was selected as a model reaction and the effect of different conditions, including the optimal amount of the catalyst, the optimal conditions with or without solvent, and temperature were investigated. Then other derivatives were synthesized in optimal conditions. The advantages of this method are high yield, less reaction time, easier separation and the use of an environmentally friendly catalyst.

In this study, 2-amino-3-cyano-4H-pyran derivatives were prepared through the three‐component condensation reaction between dimedone, aromatic aldehydes, and malononitrile in the presence of magnetic raffinose nanocomposite as green, biocompatible, and heterogeneous catalyst. The desired products were achieved within 10-30 minutes with yields of 80-95 percent. Synthetic nanocomposite has been characterized by conventional methods including Fourier Transforms InfraRed (FT‐IR) spectroscopy, Energy Dispersive X-ray (EDX) analysis, Scanning Electron Microscopy (SEM) images, Field Emission Scanning Electron Microscopy (FESEM), Vibrating Sample Magnetometer (VSM), and X-Ray Diffraction (XRD) pattern. This protocol has advantages such as mild conditions, short reaction times, simple procedure, excellent yields of the products, and purification of the products by chromatography-free methods. The magnetic properties of the nanocomposite caused its easy separation by using the external magnetic field from the reaction mixture then the catalyst was reused at least five times without a significant decrease in its catalytic activity.