a highly efficient and sustainable synthesis of 1-[(1,3-thiazol-2-ylamino) methyl]-2-naphthols under solvent-free conditions using graphene oxide substituted ethane sulfonic acid catalyst

Graphene oxide functionalized by ethane sulfonic acid (go@et-so3h) is an efficient and environmentally benign catalyst for the synthesis of 1-[(1,3-thiazol-2-ylamino) methyl]-2-naphthols. the synthesis was implemented through a one-pot process by using no solvent by the reaction of 2-naphthol, functionalized benzaldehydes, and 2-aminothiazol. first, graphene oxide was prepared according to a modified hummers method. it was subsequently modified by 2-hydroxyethyl disulfide, and then oxidized with performic acid to reach the catalyst (go@et-so3h). the catalyst was characterized by x-ray diffraction (xrd), energy-dispersive x-ray spectroscopy (eds), field emission scanning electron microscopy (fe-sem), thermogravimetric analysis (tga), and ft-ir spectroscopy. the catalyst exhibited efficient properties such as simple work-up, no byproducts, sustainability, nonmetal and safe components, stability under reaction conditions, and recoverability.