TiO2 Nanoparticles: A Potent ‎Heterogenous Nanocatalyst Mediated ‎One-Pot Tandem Approach for the ‎Environmentally Friendly Synthesis of 3,4-‎Dihydropyrimidin-2-(1H)-One/Thione ‎Derivatives Under Solvent-Free Conditions

   This procedure has developed the use of TiO2 nanoparticles as an environmentally friendly and highly efficient heterogenous nanocatalyst for the eco-safe, facile and one-pot three-component Biginelli synthesis of biologically active corresponding 3,4-dihydropyrimidin-2-(1H)-one/thione derivatives under solvent-free conditions. This eco-friendly protocol provides high to excellent yields, short reaction times, clean reaction, simplicity and easy work up and mild conditions compared to the traditional method of synthesis. Furthermore, environment-friendly, readily available, low-cost and non-toxic nanocatalyst made this protocol economic and sustainable.