TiO2/porous carbon nanocomposite as a biowaste-derived heterogeneous catalyst for the multicomponent synthesis of pyrimido[4,5-b] quinolones

Abstract

In the presented work, peanut shell was used as one of the cheap agricultural wastes for the preparation of porous carbon to design of TiO₂/porous carbon nanocomposite (TiO₂/PCN) by its thermal decomposition with nano titanium dioxide. The synergic effect of porous carbon to the catalytic ability of titanium dioxide in the structure of TiO₂/PCN is one of the most important advantages of the designed nanocomposite. The structure of the prepared nanocomposite was characterized by some analyses such as fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), Brunauer–Emmett–Teller (BET) Adsorption Isotherm, X-ray diffraction (XRD) and atomic absorption spectroscopy. TiO₂/PCN was successfully used as a heterogeneous catalyst for the synthesis of pyrimido[4,5-b] quinolines by the reaction of various aromatic aldehyde with 6-amino-1,3-dimethyluracil and dimedone in high yields (75–95%) and short reaction times.