Fe₃O₄@TiO₂@O₂PO₂(CH₂)NHSO₃H as a novel nanomagnetic catalyst: Application to the preparation of 2‐amino‐4,6‐diphenylnicotinonitriles via anomeric‐based oxidation

Abstract

A new, green and reusable nanomagnetic heterogeneous catalyst, namely Fe 3 O 4 @TiO 2 @O 2 PO 2 (CH 2 )NHSO 3 H, was synthesized and fully characterized using suitable techniques such as infrared spectroscopy, X-ray diffraction, scanning and transmission electron microscopies, thermogravimetry, vibrating sample magnetometry and energy-dispersive X-ray spectroscopy. The applicability of the constructed heterogeneous core-shell catalyst as a promoter was successfully explored for the synthesis of 2-amino-4,6-diphenylnicotinonitrile derivatives upon the reaction of a good range of aromatic aldehydes, acetophenone derivatives, malononitrile and ammonium acetate. The desired products were obtained with good to high yields in short reaction times under solvent-free conditions. The suggested mechanism offers an anomeric-based oxidation route to the products in the final step of the synthetic pathway. KEYWORDS 2-amino-4,6-diphenylnicotinonitriles, anomeric-based oxidation, Fe 3 O 4 @TiO 2 @O 2 PO 2 (CH 2 )NHSO 3 H, nanomagnetic heterogeneous catalyst, solvent-free and benign conditions

Boehmite@tryptophan‐Pd nanoparticles: A new catalyst for C–C bond formation

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