Popis: |
The cellulose grafted to chitosan by ethylenediaminetetraacetic acid (Cs-EDTA-Cell) material was prepared and characterized by different spectroscopic, microscopic or analytical methods and techniques including Fourier transform infrared (FTIR) and ultraviolet–visible diffuse reflectance (UV–Vis-DRS) spectroscopy, field emission scanning electron microscopy (FESEM), and X-ray powder diffraction (XRD) as well as Brunauer-Emmett-Teller (BET) surface area, thermogravimetric, and differential thermal analysis. The obtained Cs-EDTA-Cell network was found to be more thermally stable than its original carbohydrate polymers components. The bio-based Cs-EDTA-Cell network contains appropriate acidic and basic active sites with proper geometry to act as a multifunctional organocatalyst at nanoscale. The synergic effect of Cs-EDTA-Cell network components were demonstrated to promote multicomponent synthesis of polyhydroquinoline and 1,8-dioxo-decahydroacridine derivatives under green and environmentally-benign conditions. A large number of fused Hantzsch esters were synthesized using low catalyst loading, in high to excellent yields, short reaction times, and simple work-up procedure. Furthermore, the Cs-EDTA-Cell network, as a heterogeneous catalyst, demonstrated excellent reusability and can be used at least for five consecutive runs without significant loss of its activity. |