Solvent-free Synthesis of Novel Benzothiazole-substituted 4-Thiazolidinones Using Nano Silica-bonded 5-n-Propyl-octahydro-pyrimido[1,2-a]azepinium Chloride as Catalyst
A series of novel benzothiazole-substituted 4-thiazolidinones were synthesised by the one-pot reaction of rhodanine-3-acetic acid derivatives, 2-aminothiophenol, and triphenyl phosphite in the presence of nano silica-bonded 5-n-propyl-octahydro-pyrimido[1,2-a]azepinium chloride (NSB-DBU) as heterogeneous reusable nanocatalyst under solvent-free conditions in high yields.