Behzad Zeynizadeh*, Soleiman Rahmani and Arezu Hallaj Pages 1 - 9 ( 9 )
Aim and Objective: Nowadays, bisdimedones and 1,8-dioxo-octahydroxanthenes are considered as biological active materials. Due this, synthesis of the mentioned materials is a subject of more interest. Although most of the reported methods have the own merits, however, they generally suffer from using expensive reagents, hazardous organic solvents, tedious workup procedure and reduced recyclability of the applied catalyst system. Overcoming of the titled drawbacks, therefore, encouraged us to investigate the capability of nanostructured NiFe2O4@Cu towards synthesis of bisdimedones and 1,8-dioxo-octahydroxanthenes under green reaction conditions.
Materials and Methods: Nanoparticles of NiFe2O4@Cu were prepared via a two-step procedure including the preparation of NiFe2O4 by solid-state grinding of Ni(OAc)2·4H2O and Fe(NO3)3·9H2O in the presence of NaOH followed with the immobilization of Cu(0) on the surface of NiFe2O4 nucleus via hydrazine hydrate reduction of Cu(NO3)2·3H2O.
Results: After synthesis of NiFe2O4@Cu, catalytic activity of the Cu-nanocatalyst towards Knoevenagel reaction of aromatic aldehydes with dimedone under different reaction conditions was investigated. The examinations resulted that using the molar equivalents of aromatic aldehydes (1 mmol) and dimedone (2 mmol) in the presence of 0.15 g NiFe2O4@Cu under solvent-free conditions chemoselectively afforded structurally different bisdimedone products at 60 °C and 1,8-dioxo-octahydroxanthenes at 120 °C.
Conclusion: In this study, magnetically nanoparticles of NiFe2O4@Cu were prepared and then characterized using different analyses. Catalytic activity of the prepared Cu-nanocatalyst was also studied towards solvent-free Knoevenagel condensation of aromatic aldehydes with dimedone. All reactions were carried out within 15‒240 min to afford bisdimedone and 1,8-dioxo-octahydroxanthene products in high yields.
Bisdimedone, 1, 8-dioxo-octahydroxanthene, Knoevenagel, NiFe2O4@Cu, solvent-free
Faculty of Chemistry, Urmia University, Urmia 5756151818, Faculty of Chemistry, Urmia University, Urmia 5756151818, Faculty of Chemistry, Urmia University, Urmia 5756151818