An efficient protocol for the synthesis of oxazine derivatives using a carbocatalyst in aqueous medium

Abstract

Reduced graphene oxide (rGO) is a suitable alternative to toxic metal-based catalysts, due to its large surface area, sp² carbon backbone and oxygen functionalities that can interact with organic moieties and disperse in water. We have reported herein the synthesis of 1,3-oxazines via multicomponent reaction of various amines, formaldehyde and sesamol/2-hydroxy-1,4-naphthaquinone/6-hydroxyquinoline in aqueous medium for the first time using rGO as the catalyst at 80 °C. The reactions were complete in 5–15 min and afforded the products in excellent yields. Short reaction time, easy separation of recyclable catalyst and green methodology are advantages of this protocol.

Graphical Abstract

Keywords:

• Green methodology
• 1,3-oxazines
• phenolic compounds
• reuse
• rGO

Acknowledgements

S.G. is thankful to UGC, New Delhi, India for the award of Junior and Senior Research Fellowship.