Green Aqueous Synthesis of Mono, Bis and Trisdihydropyridines Using Nano Fe3O4 Under Ultrasound Irradiation (original) (raw)

Ultrasound‐Assisted Green Synthesis of Pyrrole‐Fused Pyrimidine and Imidazole Rings through a Tandem Pseudo‐Four‐Component Reaction

ChemistrySelect, 2022

A green and efficient method for the preparation of 5-aryl-4-hydroxy-2-methyl-1H-pyrrole-3carboxylic acid esters and 6-aryl-3-methylpyridazine-4-carboxylic acid esters via threecomponent reaction of arylglyoxal hydrates with β-dicarbonyl compounds in the presence of ammonium acetate and hydrazine hydrate using water as solvent under ultrasonic irradiation was reported. The reactions proceeded rapidly and afforded the corresponding pyrroles and pyridazines in good to high yields in very short reaction time.

Ultrasound-assisted green synthesis of pyrroles and pyridazines in water via three-component condensation reactions of arylglyoxals

Current Chemistry Letters, 2013

A green and efficient method for the preparation of 5-aryl-4-hydroxy-2-methyl-1H-pyrrole-3carboxylic acid esters and 6-aryl-3-methylpyridazine-4-carboxylic acid esters via threecomponent reaction of arylglyoxal hydrates with β-dicarbonyl compounds in the presence of ammonium acetate and hydrazine hydrate using water as solvent under ultrasonic irradiation was reported. The reactions proceeded rapidly and afforded the corresponding pyrroles and pyridazines in good to high yields in very short reaction time.

An Efficient and Green Synthesis of 6-Amino-3-phenyl-4-aryl-1,4-dihydropyrano [2,3-c]pyrazole-5-carbonitrile Derivatives under Ultrasound Irradiation in Aqueous Medium

Journal of Heterocyclic Chemistry, 2013

A facile and eco-friendly approach for the synthesis of 6-amino-3-phenyl-4-aryl-1,4-dihydropyrano[2,3-c] pyrazole-5-carbonitrile derivatives via four-component reaction of hydrazine, ethyl 3-oxo-3-phenylpropanoate, aldehydes, and malononitrile is described. The reaction is performed in water, without using any catalyst, and under ultrasound irradiation. The developed sonochemical-assisted multi-component reaction provides an improved and accelerated conversion when compared with conventional procedure.

Ultrasound-Promoted One-Pot, Four-Component Synthesis of Pyridin-2(1H)-One Derivatives

Molecules, 2013

An efficient one-pot synthesis of 1,6-diamino-2-oxo-1,2,3,4-tetrahydropyridine-3,5-dicarbonitrile derivatives by four-component piperidine-catalyzed reactions of a ketone, malononitrile, ethyl cyanoacetate and hydrazine hydrate under ultrasound irradiation is described. This method provides several advantages such as shorter reaction times, excellent yields, and a simple workup procedure.

Convenient syntheses of pyrazolo[3,4-b]pyridin-6-ones using either microwave or ultrasound irradiation

Tetrahedron Letters, 2011

An efficient synthesis of 12 pyrazolo [3,4-b]pyridin-6-one derivatives was achieved using either microwave or ultrasound irradiation, resulting in yields of 40-60% and 60-95%, respectively. Under our conditions, these reactions occurred with notably reduced reaction times as compared to literature reports involving traditional heating. Furthermore, these reactions were highly regioselective and produced only one pyrazolo [3,4-b]pyridin-6-one isomer, whose identity was confirmed by NOESY spectroscopy.

ULTRASOUND-MEDIATED SYNTHESIS OF 2,4,6-TRIARYL- PYRIDINES USING MgAl 2 O 4 NANOSTRUCTURES

Nanocrystalline MgAl 2 O 4 was found to be a highly efficient catalyst for the preparation of 2,4,6-triaryl-pyridines from the reaction of acetophenone derivatives, aryl aldehydes, and ammonium acetate under sonic condition for the first time. The present methodology offers several advantages, such as excellent yields, simple procedure, shorter reaction times, and milder conditions; the catalyst also exhibited remarkable reusable activity. This procedure is much simpler and faster than the protocols published to date.

Ultrasound-assisted synthesis of imidazo[1,2-a]pyridines and sequential one-pot preparation of 3-selanyl-imidazo[1,2-a]pyridine derivatives

Arkivoc, 2019

A simple and rapid method to synthesize imidazo[1,2-a]pyridines starting from 2-aminopyridine and 2bromoacetophenone derivatives under ultrasonic irradiation was developed. This protocol tolerates a wide range of 2-bromoacetophenone derivatives to produce a variety of imidazo[1,2-a]pyridines in good to excellent yields. Additionally, the one-pot preparation of 3-(organylselanyl)imidazo[1,2-a]pyridines via a sequential method is presented. In this case, different diorganyl diselenides were used as starting material s to afford the corresponding coupling products in excellent yields and short reaction times under sonication. The reactions were conducted in PEG-400, a cheap and nontoxic solvent, compatible with the ultrasound conditions in an environmentally benign process.