Rapid and Efficient One-Pot Synthesis of 3,4-Dihydroquinoxalin-2-Amine Derivatives Catalyzed by Co₃O₄@SiO₂ Core-Shell Nanoparticles Under Ultrasound Irradiation

Abstract

In this research, a general synthetic method for the synthesis of 3,4- dihydroquinoxalin-2-amine derivatives was developed using Co3O4@SiO2 nanoparticles under ultrasonic irradiation. Firstly by a simple and green process, Co3O4;@SiO2 nanoparticles were prepared via sonication, and then these nanoparticles were used as an efficient catalyst for the synthesis of 3,4- dihydroquinoxalin-2-amines via three-component reactions of ophenylenediamines (OPDA), diverse ketones and various isocyanides in ethanol under ultrasound irradiation. The combinatorial synthesis was attained for this procedure with applying ultrasound irradiation while making use of ethanol as green ambient. The present approach offers several advantages such as high yields, environmentally benign, simple work-up, excellent yield of products and short reaction times. The nanomagnetic catalyst could be readily recovered using a simple external magnet and reused several times without any significant loss in activity. The catalyst was fully characterized by FT-IR, FE-SEM, XRD, EDX, VSM and TEM analysis.

Greener organic synthetic methods: Sonochemistry and heterogeneous catalysis promoted multicomponent reactions

“…As already reported in several works cited throughout this review, magnetic nanoparticles assumed a prominent role in the scenario of heterogeneous catalysis. In this context, Ghasemzadeh et al [159] have developed a greener ultrasound-assisted method to synthesize a series of dihydroquinoxalines ( 50 ) via a three-component reaction of o -penylenediamines ( 48 ), ketones ( 8 ) and isocyanides ( 49 ) in the presence of EtOH, using a magnetic Co 3 O 4 nanocatalyst embedded in silica (Co 3 O 4 @SiO 2 , 5 mol%) ( Scheme 19 ). The reactions were sonicated at 40 kHz frequency and 80 W power at room temperature.…”

Synthesis and Antibacterial Evaluation of Some New 1,4-Dihydropyridines in the Presence of Fe3O4@Silica Sulfonic Acid Nanocomposite as Catalyst

“…In recent years, the magnetically sulfonic acids were applied as an effective nanocatalyst in many organic reactions such as: preparation of 3,6-di(pyridin-3-yl)-1H-pyrazolo [3,4-b]pyridine-5-carbonitriles, 24 pyrano coumarins, 25 amides, 26 quinazoline derivatives, 27 and formylation of alcohols and amines. 28 In continue of our attempts towards the improvement of the synthetic methods using heterogeneous catalysts, [29][30][31][32][33] Here we report a new and efficient pathway for the preparation of 1,4-DHPs via multi-component synthesis of arylamine, dimethyl acetylenedicarboxylate, aromatic aldehyde and ethyl acetoacetate by using Fe 3 O 4 @silica sulfuric acid core-shell nanocomposite (Scheme 1).…”

NiCo2O4@Ni(BDC) Nano‐Porous Metal–Organic Framework as a Novel Catalyst for the Synthesis of Spiro[indene[1,2‐d]pyrimidine‐ones and Investigation of Their Antimicrobial Activities

“…Herein, in continuation of the progress of the synthetic approach for the preparation of various heterocyclic compounds with biological activities, we wish to report the synthesis pyrimidine derivatives using a metal‐organic framework NiCo 2 O 4 @Ni(BDC) as a novel, efficient and green heterogeneous catalyst (Scheme ) . Moreover, we successfully evaluated the antibacterial and antifungal activities of the synthesized pyrimidine derivatives via disk diffusion method.…”