One-pot Multicomponent Synthesis of pyrrolo[1,2-d][1,4]benzoxazines and pyrrolo[1, 2-a]pyrazines in Water Catalyzed by Fe3O4@SiO2@L-Arginine-SA Magnetic Nanoparticles.

Abstract

Synthesis of pyrrolo[1,2-d][1,4]benzoxazines and pyrrolo[1,2-a]pyrazines using magnetic nanoparticles. One-pot, three component reaction for the synthesis of pyrrolo[1,2-d][1,4]benzoxazines and pyrrolo[1,2-a]pyrazines is reported. For the synthesis of pyrrolo[1,2-d][1,4]benzoxazines use of 2- aminophenols, dialkylacetylenedicarboxylates and β -nitrostyrene derivatives and Pyrrolo[1,2-a]pyrazines synthesized from reaction of ethylenediamine, dialkylacetylenedicarboxylates and β-nitrostyrene derivatives is discussed. 2-aminophenol (0.5 mmol) and dimethylacetylenedicarboxylate (0.5 mmol) in water (3 ml) were stirred at room temperature for 10 min. Then, β-nitrostyrene (0.5 mmol) and Fe3O4@SiO2@LArginine- SA MNPs (0.07 g) were added and the mixture was refluxed for 5 h. After completion of the reaction, the mixture was cooled to room temperature and the catalyst was separated with external magnet and product extracted with dichloromethane. More purification of products was performed by column chromatography (nhexane/ ethyl acetate 4:1). Ethylenediamine (0.6 mmol) was added to dialkylacetylenedicarboxylate (0.6 mmol) in 3 ml water and was stirred for 10 min at room temperature. Later, β -nitrostyrene (0.5 mmol) and Fe3O4@SiO2@L-Arginine-SA MNPs (0.06 g) were added to mixture reaction and refluxed for 3 h. After completion, the mixture reaction was cooled to room temperature and the catalyst was separated by an external magnet. Then, the product was extracted with dichloromethane. For more purification column chromatography was used (n-hexane/ethylacetate 1:1). In this research, we have synthesized new derivatives of pyrrolo[1,2- d][1.4]benzoxazines and pyrrolo[1,2-a]pyrazines in green conditions consisting of use of water as a green solvent and magnetic nanoparticles. In this research, we have synthesized new derivatives of pyrrolo[1,2-d][1.4]benzoxazines and pyrrolo[1,2-a]pyrazines in green conditions consisting of use of water as a green solvent and magnetic nanoparticles which were easily separated from mixture with an external magnet and had the capability to be recovered and reused. Also, in this work, the yield was good and the time of reactions was low compared with prior research.