Synthesis of Bioactive Polyhydroquinolines Using Sulfated Tin Oxide as an Efficient Solid Superacid Catalyst

Abstract

A novel synthetic scheme has been designed for the synthesis of polyhydroquinoline derivatives via one-pot condensation of aromatic aldehydes, EAA, dimedone, and NH4OAc by employing synthesized STO as a heterogeneous solid acid catalyst in ethanol under reflux condition. FTIR, XRD, and SEM EDX were used to confirm the sulfated tin oxide. BET plots were used to analyze the surface area of the catalyst. The reactions were assessed for diverse solvents and catalyst loading. The yields of all the polyhydroquinoline derivatives were found to range between 80 to 92%. All the synthesized polyhydroquinolines were validated by spectral data. This exercise is efficient and green as it uses an environmentally friendly catalyst, has a significant atom economy, is cost-effective and easy to work up.