A Simple and Efficient One‐pot Synthesis of 1,4‐dihydropyridines Using Nano‐WO₃‐ supported Sulfonic Acid as an Heterogeneous Catalyst under Solvent‐free Conditions

Abstract

Nano-tungsten trioxide-supported sulfonic acid (n-WSA) was found to be an effective heterogeneous catalyst for the one-pot reaction of aromatic aldehydes, b-dicarbonyl compounds and ammonium acetate to afford 1,4-dihydropyridine derivatives in good to excellent yields. The other main advantages of the present method are short reaction times, simple workup, ease in purification and environmentally benign methodology. The reaction conditions were optimized employing Response Surface Method technique (Central Composite Design (CCD)) which is economically considerable because of the minimum number of experiments required to evaluate the effects of multiple parameters on the response.

One-pot multicomponent green Hantzsch synthesis of 1,2-dihydropyridine derivatives with antiproliferative activity

“…These two factors will reduce the amount of hazardous chemicals by reducing the amount of solvent in the reactor and during the workup of the product. A solid insoluble catalyst can easily be removed from the reaction mixture via filtration, unlike a soluble one [23][24][25].…”

Sulfamic Acid‐functionalized Nano‐titanium dioxide as a Novel and Highly Efficient Heterogeneous Nanocatalyst for One‐pot and Solvent‐free Synthesis of Hexahydroquinolines

“…In this paper, in continuation of our studies on applying green catalysts for organic transformations, we investigate the catalytic activity of nano (n)‐TiO 2 ‐NHSO 3 H for the synthesis of hexahydroquinolines (Scheme ).…”

Nano‐WO3‐SO3H as a New Photocatalyst Insight Through Covalently Grafted Brønsted Acid: Highly Efficient Selective Oxidation of Benzyl Alcohols to Aldehydes

“…This new heterogeneous solid acid nano catalyst established a new vision in development of catalytic activity of WO 3 . This efficient and retrievable catalyst which was derived through a quick method for heterogenization of homogeneous catalysts, could be operated in some organic reactions such as synthesis of 1,8‐dioxo‐octahydroxanthene, tetrahydrobenzoxanthene, benzimidazole quinazolinone derivatives and also synthesis of 1,4‐dihydropyridines under solvent‐free conditions . In our recent study, nano‐TiO 2 ‐P25‐SO 3 H introduced as a novel and powerful photocatalyst, for the first time.…”