Efficient and Mild Synthesis of Pyranopyrimidines Catalyzed by Decorated Multi-walled Carbon Nanotubes Bearing Cobalt, Nickel, and Copper Metals in Water

The multicomponent reactions (MCRs) produce one compound from three or more reactants. Due to the innumerable combination possibilities of reagents, MCRs are popular because of their simplicity and versatility. In this research, an one-pot three-components reaction was carried out between 1,3-diethyl barbituric acid, malononitrile, and aldehydes in the presence of Cu/Co/Ni/MWCNTs as a recyclable catalyst. This catalyst indicated high catalytic activity with good proficiency and reusability under mild condition. This method proposed numerous materials such as being environmentally amicable in high product yields and short reaction times at ambient temperature. The catalysts were collected and specified by diverse spectroscopic techniques such as; FT-IR, X-ray diffraction, and scanning electron microscopy. After finalizing the reaction, the resulted compounds purified, and identified by the melting points, infrared spectroscopy (FT-IR), and the magnetic resonance of the hydrogen nucleus (H-1 NMR) techniques.