As a natural-based catalyst, nano-Fe3O4@dextrin/Si(CH2)3/DABCO was fabricated and characterized with different analytical methods such as field emission scanning electron microscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, X-ray mapping, energy-dispersive X-ray spectroscopy, thermogravimetric analysis, and vibrating sample magnetometer. The mentioned new natural magnetic nanocatalyst was employed for the three-component synthesis of tetrahydrobenzo[b]pyrans and spirooxindoles from aromatic aldehyde […]
An one-pot method has been developed for the synthesis of azo dyes via sequential diazotization–diazo coupling of aromatic amines with coupling agents at room temperature in the presence of Bi(NO3)3. 5H2O. Short reaction times, high yields, a clean process, simple methodology, easy work-up and green conditions are advantages of this protocol.