Nano-BF3/cellulose as a biodegradable novel catalyst for synthesis of highly functionalized tetrahydropyridines

Nano-cellulose with high amount of free OH groups could be used as supporting agents for boron trifluoride (BF3). Nano-BF3/cellulose is a solid acid and a biodegradable catalyst which was prepared via reaction of nano-cellulose and BF3. The structure of this catalyst was studied by FT-IR, FESEM, TEM, XRD, EDS, TGA, XRF and BET. In this research, the synthesis of highly functionalized tetrahydropyridines has been developed via a five-component reaction of aldehyde, amine and ethyl acetoacetate using nano-BF3/cellulose under solvent-free conditions. The structures of obtained products were identified by FTIR, 1H NMR and 13C NMR. Some advantages of this protocol are high to good yields, environmentally benign procedure, easy work-up of reaction and moderate reusability of the catalyst.