Visible light-induced synthesis of benzothiazole derivatives using graphitic carbon nitride as a recyclable metal-free photocatalyst

Abstract

The utilization of visible light irradiation in organic synthesis has garnered significant attention due to its environmentally friendly nature and efficiency. In this study, we explore the application of graphitic carbon nitride (g-C₃N₄) as a photocatalyst for the synthesis of 2-Arylbenzothiazole under visible light irradiation. The reaction conditions were optimized to achieve high yields (89–97%) and selectivity of products. Characterization techniques such as FTIR spectroscopy, X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and UV–Vis Diffuse Reflectance Spectra (DRS) were employed to analyze the catalyst structure. The results demonstrated that g-C₃N₄ acted as an effective photocatalyst, facilitating the synthesis of benzothiazole with excellent yields (89–97%). This approach marks a notable improvement over prior methodologies, leading to significantly faster reaction times and improved yields. Additionally, the exceptional recyclability of g-C₃N₄ allows it to be reused in multiple reaction cycles without significant loss of activity, which is a crucial factor in reducing waste and resource consumption, facilitating a greener process. Consequently, it highlights g-C₃N₄’s potential for sustainable and eco-friendly synthesis of 2-Arylbenzothiazole and other valuable organic compounds.

Graphical abstract

• The g-C₃N₄ was synthesized by thermal polymerization of urea, and was characterized through several technique such as XRD, FTIR, SEM, and DRS.

• g-C₃N₄ was used as highly efficient photocatalyst of 2-arylbenzothiazole under visible light irradiation.

• Benzothiazoles were successfully prepared, yielding 89–97% in a brief stirring time of 5–15 min.

• g-C₃N₄ continued to exhibit high catalytic activity after being recycled multiple times, without any significant degradation.