Eco-Friendly Synthesis of Quinazoline Derivatives Through Visible Light-Driven Photocatalysis Using Curcumin-Sensitized Titanium Dioxide

This study explores a sustainable method for synthesizing quinazoline derivatives through visible light-driven photocatalysis using curcumin-sensitized titanium dioxide (TiO₂) nanoparticles. A one-pot, three-component reaction involving aldehydes, urea/thiourea, and dimedone was utilized to efficiently produce quinazoline compounds. The photocatalytic performance of curcumin-sensitized TiO₂ (Cur-TiO₂) was compared to pure TiO₂ (P-TiO₂), with Cur-TiO₂ showing significantly enhanced activity. Under optimized conditions—light intensity of 100 mW/cm², catalyst concentration of 1 mg/mL, and a reaction time of 40 min—a 97% product yield was achieved. The Cur-TiO₂ catalyst demonstrated excellent reusability, maintaining high efficiency over four consecutive cycles with minimal performance loss. This work underscores the potential of natural dye sensitization to extend light absorption of TiO₂ into the visible spectrum, providing an eco-friendly and cost-effective approach to sustainable organic synthesis.