Iodine-catalyzed three-component one-pot synthesis of naphthopyranopyrimidines under solvent-free conditions

Iodine is found to be a highly efficient catalyst for the three-component coupling (3CC) of aldehydes, β-naphthol, and 1,3-dimethylbarbituric acid under solvent-free conditions to afford the corresponding 8,10-dimethyl-12-aryl-12H-naphtho[1′,2′5,6]pyrano[2,3-d]pyrimidine-9,11-diones in good yields with high selectivity. The use of readily available iodine makes this method very simple, convenient, and cost-effective.     

Synthesis of 3-aminoisoxazolmethylnaphthols via one-pot three-component reaction under solvent-free conditions

A one-pot three-component condensation reaction of 3-amino-5-methylisoxazole, aryl aldehyde and 2-naphthol to afford the corresponding 3-amino isoxazolmethylnaphthols in good to excellent yields. The remarkable features of this new procedure are high conversions, clean reaction condition, short reaction time, nonhazardous and environmentally friendly reaction condition, inexpensive and easily commercially availability of the catalyst and simple work-up procedures.     

Synthesis of thiohydantoins under one-pot three-component solvent-free conditions

A direct and efficient one-pot three-component synthesis protocol was developed for the synthesis of thiohydantoins from readily and widely available substrates (isothiocyanates, ethyl chloroacetate, and amines) employing solvent-free conditions. Correspondence: Song Cao, Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China.     

A novel polymeric catalyst for the one-pot synthesis of xanthene derivatives under solvent-free conditions

A simple, efficient, and environmentally benign route was developed for the preparation of 14-aryl or alkyl-14H-dibenzo[a,j]xanthene, 1,8-dioxo-octahydroxanthene and 12-aryl??8,9,10,12-tetrahydrobenzo[a]xanthene-11-ones from condensation of various aldehydes with (i) ??-naphthol, (ii) cyclic 1,3-dicarbonyl compounds and (iii) ??-naphthol and cyclic 1,3-dicarbonyl compounds, using novel polymeric catalyst [poly(AMPS-co-AA)] under solvent-free conditions. Use of easily available catalyst, shorter reaction times, better yields, simplicity of the reaction, heterogeneous system, and easy work-up are the advantages of the present method.     

Microwave-assisted efficient, one-pot, three-component synthesis of 3,5-disubstituted 1,2,4-oxadiazoles under solvent-free conditions

A novel synthesis of 1,2,4-oxadiazoles is described from a one-pot, three-component reaction between nitriles, hydroxylamine, and aldehydes under microwave irradiation and solvent-free conditions in excellent yields.     

Microwave promoted solvent-free one-pot three-component reaction to 2-pentafluorophenylquinoline derivatives

A novel and efficient one-pot multi-component reaction of pentafluorobenzaldehyde, alkynes and anilines for the synthesis of 2-pentafluorophenyl substituted quinolines under microwave irradiation and a solvent-free condition is presented.     

TfOH/C-catalyzed one-pot three-component synthesis of α-amino phosphonates under solvent-free conditions

The TfOH/C was readily prepared via simple absorption of triflic acid onto activated charcoal. This solid acid was used as an efficient catalyst for the synthesis of α-aminophosphonates through the Kabachnik–Fields reaction of carbonyl compound, amine and diethyl phosphite under solvent-free conditions.     

A green and convenient protocol for the synthesis of diarylmethanes via a one-pot,three-component reaction catalyzed by a novel silica tungstic acid (STA) under solvent-free conditions

A cost-effective and eco-friendly synthesis of diarylmethanes derivatives has been developed through the Mannich type Friedel–Crafts addition reaction of tertiary aromatic amine formaldehydes with β-naphthol/indole using silica-supported tungstic acid (STA) as a recyclable heterogeneous acid catalyst in solvent-free condition. Here, we proposed two schemes using the same catalyst. The effects of different solvents have been studied and a comparison of silica-supported tungstic acid with different acid catalysts has also been made.     

Synthesis of novel isoindolone derivatives via cascade reactions. Contrasting diastereoselectivity under solution-phase vis-a-vis solvent-free ball-milling reaction conditions

The highly diastereoselective synthesis, crystallographic analysis, and full characterization of several novel heterocycle-fused isoindolones is described. The synthetic strategy involves a cascade Michael/aldol-like cyclization reaction between N-substituted phthalimides rac-1 or 2 and several α,β-unsaturated electrophiles to afford the tricyclic systems pyrrolo[2,1- a]isoindolone and tetrahydropyrido[2,1-a]isoindolone. This synthetic strategy offers a convenient alternative to existing procedures for the preparation of isoindolone derivatives fused to five- and six-membered rings. X-ray crystallographic analysis allowed the determination of relative configurations and revealed that the synthesized compounds exhibit significant structural distortion, especially in the five membered rings. Relevantly, the diastereomeric distribution of products depends substantially on whether the cascade reaction is carried out under solution vis-a-vis solvent-free conditions.     

One-pot three-component Mannich reaction catalyzed by iodine under solvent-free conditions

One-pot three-component Mannich reactions of ketones with aromatic aldehydes and aromatic amines are effectively catalyzed by molecular iodine at room temperature under solvent-free conditions to afford the corresponding β-amino carbonyl compounds with moderate to excellent yields. The method has the following advantages: no use of solvent, mild condition, high reaction speed and small quantity of catalyst.     

Eco-friendly solvent-free synthesis of thiazolylpyrazole derivatives

Highly versatile ethyl 3-thiosemicarbazidobutanoate was ball-milled with phenacyl bromide to afford the corresponding ethyl 3-[(4-phenyl-2-thiazolyl)hydrazono]butanoate which underwent heterocyclization by heating in ethanolic sodium acetate to give thiazolylpyrazolone that coupled chemoselectively with aromatic diazonium salts to furnish arylhydrazonothiazolylpyrazoles. Vilsmeier-Haack reaction of ethyl 3-thiosemicarbazidobutanoate furnished selectively thiazolylpyrazole. A series of pyrazolylthiosemicarbazones were synthesized by solid-state technique which allowed waste-free production. The reaction of pyrazolylthiosemicarbazones with phenacyl bromide afforded the corresponding 2-(arylidenehydrazino)-4-phenylthiazoles in quantitative yields. Correspondence: Samir Bondock, Department of Chemistry, Faculty of Science, Mansoura University, ET-31556 Mansoura, Egypt.     

A one-pot three-component reaction to access 1-alkyl-2-aryl-5-nitrobenzimidazoles under solvent-free conditions

A novel and expeditious method to access 1-alkyl-2-aryl-5-nitrobenzimidazoles has been developed. Enlisting solvent-free conditions, 2-fluoro-5-nitroaniline, a primary amine, and substituted aldehyde were melted together in one-pot to generate a variety of 1-alkyl-2-aryl-5-nitrobenzimidazoles.     

A novel one-pot, three-component reaction for the synthesis of isocoumarin-condensed pyrazoles

The one-pot, three-component reaction of substituted homophthalic anhydrides with hydrazine in DMF as solvent and reactant, at reflux temperature, afforded isochromeno[3,4-c]pyrazole-5(2H)-one derivatives in high yields. The mechanism and roles of the substrates were investigated and it was found that cyclic hydrazides were formed as intermediates.     

A novel one-pot synthesis of tetrasubstituted imidazoles under solvent-free conditions and microwave irradiation

The one-pot, three-component condensation of benzil, benzonitrile derivatives and primary amines on the surface of silica gel under solvent-free conditions and microwave irradiation provided tetrasubstituted imidazoles in high yields.     

One-pot three-component Mannich-type reaction catalyzed by trifluoromethanesulfonic acid in water

One-pot three-component Mannich-type reaction of ketones, aldehydes and amines was efficiently catalyzed by liquid trifluoromethanesulfonic acid in water at ambient temperature. The high yield of corresponding β-amino ketones compounds were achieved. The proposed method is mild, green, simple and efficient.     

Efficient synthesis of pyrimidinone derivatives by ytterbium chloride catalyzed Biginelli-type reaction under solvent-free conditions

An efficient and clean method was developed for the one-pot synthesis of pyrimidinones by ytterbium chloride catalyzed Biginelli-type reaction of aromatic aldehyde, cyclopentanone, and urea or thiourea under solvent-free conditions.     

SnCl2-catalyzed three-component one-pot Mannich-type reaction: efficient synthesis of β-aminocarbonyl compounds

Abstract  

SnCl₂-catalyzed three-component one-pot Mannich reaction of acetophenone or p-chloroacetophenone with different aromatic aldehydes and aromatic amines in ethanol at ambient temperature gave the corresponding β-aminocarbonyl compounds in good to excellent yields. Four new compounds are reported for the first time.     

无溶剂条件下碳基固体酸催化一锅法合成酰胺烷基萘酚(英文)

An efficient, environmentally friendly procedure for the synthesis of amidoalkyl naphthols through the one‐pot, three‐component reaction of β‐naphthol, aryl aldehydes, and acetamide in the presence of a carbon‐based solid acid under thermal solvent‐free conditions is described. The beneficial fea-tures of this new synthetic approach include short reaction time, high yields, clean reaction profiles, and a simple work‐up procedure. Furthermore, the catalyst can be readily recycled and reused four times without obvious significant loss of activity. The structure of the catalyst was confirmed by Fourier transform infrared spectroscopy, N2 adsorption/desorption analysis, and X‐ray diffraction.