TiO2 nanoparticles/melamine Tri sulfonic acid for biginelli syntheis under solvent-free conditions

TiO2 nanoparticles/melamine Tri sulfonic acid (MTSA) supported on silica gel as an efficient catalytic system for simple, one pot, solvent-free and environmentally benign process for synthesis of dihydropyrimidines via Biginelli reaction at 110 °C is described. It was found that the catalyst is reusable and exhibited remarkable activity. The catalyst can be easily separated and reused several times without appreciable loss of activity. The availability and recoverability of the catalytic system with easy operation and work up make this catalytic system attractive for organic synthesis.