One-pot synthesis of chromenes in the presence of nano-cellulose/Ti(IV)/Fe3O4 as natural-based magnetic nano-catalysts under solvent free conditions.

In this study, the preparation of magnetic catalysts of titanium tetrachloride stabilized on nano-cellulose named cellulose/Ti(IV)/Fe3O4 was investigated. Various methods such as XRD, SEM, FT-IR, BET, EDX, TEM, TGA and VSM were used to characterize the catalysts. Then, the identified catalysts were used for the synthesis of various chromene skeletons via reaction of malononitrile, aldehyde and dimedone, 4-hydroxycoumarine or 2-naphthole at 70 °C under solvent free conditions. The spectroscopic methods used to determine the structure of the products include 13C NMR, 1H NMR and FT-IR.