Solvent-free, one-pot synthesis of amidoalkyl naphthols by a copper p-toluenesulfonate catalyzed multicomponent reaction

Abstract  

An efficient synthesis of amidoalkyl naphthols using copper p-toluenesulfonate (CPTS) as catalyst for the three-component condensation reaction of 2-naphthol, aldehydes, and amides under thermal, solvent-free conditions is described. This new approach has advantages such as short reaction time, high yield, simple work-up, and reusable catalyst.     

A one-pot synthesis of N-alkylthiazoline-2-thiones from CS2, primary amines, and 2-chloro-1,3-dicarbonyl compounds in water

Abstract  

A simple synthesis of N-alkylthiazoline-2-thiones by reaction of primary amines, carbon disulfide, and 2-chloro-1,3-dicarbonyl compounds in water is described. Proceeding without catalyst under one-pot conditions in high yields and with broad scope, this method high synthetic utility.     

A one-pot multicomponent reaction for synthesis of 1-amidoalkyl-2-naphthols catalyzed by PEG-based dicationic acidic ionic liquids under solvent-free conditions

Abstract  

A mild and efficient method was developed for preparation of amidoalkyl naphthols via one-pot three-component condensation of aldehydes with amides and 2-naphthol in the presence of polyethylene glycol (PEG)-based dicationic acidic ionic liquid as a powerful catalyst under solvent-free conditions. Excellent yields, short reaction time, simple work-up, and reusable catalyst are advantages of this procedure.     

Sulfamic-acid-catalyzed simple and efficient synthesis of 4-aryl-3-methyl-1-phenyl-1H-benzo[g]pyrazolo[3,4-b]quinoline-5,10-diones under solvent-free conditions

Abstract  

An efficient synthesis of 4-aryl-3-methyl-1-phenyl-1H-benzo[g]pyrazolo[3,4-b]quinoline-5,10-diones from the three-component condensation reaction of 3-methyl-1-phenyl-1H-pyrazol-5-amine, aromatic aldehydes, and 2-hydroxy-1,4-naphthoquinone under solvent-free conditions in good to excellent yields and short reaction times using sulfamic acid as heterogeneous acid catalyst has been investigated.     

DBU-catalyzed expeditious and facile multicomponent synthesis of N-arylquinolines under microwave irradiation

Abstract  

N-Arylquinoline derivatives are obtained in excellent yields by a rapid, easy, and efficient one-pot multicomponent reaction of aromatic aldehydes, 3-arylamino-5,5-dimethylcyclohex-2-enone, and active methylene compounds utilizing 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) as a catalyst in ethanol under microwave irradiation.     

Nanocrystalline aluminium oxide: a mild and efficient reusable catalyst for the one-pot synthesis of poly-substituted quinolines via Friedlander hetero-annulation

Abstract  

o-Aminoaryl ketones undergo smooth condensation with α-methylene ketones in the presence of nanocrystalline aluminium oxide under mild reaction conditions to afford the corresponding poly-substituted quinolines in excellent yields. The catalyst can be recovered by simple filtration and can be recycled in subsequent reactions.     

An efficient synthesis of ferrocenyl imidazo[1,2-a]pyridines

Abstract  

An efficient and simple synthesis of ferrocenyl 3-aminoimidazo[1,2-a]pyridines by the three-component reaction of ferrocenecarboxaldehyde, isocyanides, and 2-aminopyridines in the presence of a catalytic amount of InCl₃ in ethanol at room temperature is reported.     

Synthesis of 3-aryl-4(3H)-quinazolinones from anthranilic acid, ortho esters, and anilines using Ce(CH3SO3)3·2H2O as catalyst

Abstract  

3-Aryl-4(3H)-quinazolinones were synthesized efficiently by the three component one-pot cyclocondensation of anthranilic acid, ortho esters, and anilines in the presence of Ce(CH₃SO₃)₃·2H₂O at room temperature under solvent-free conditions. This method offers several advantages, such as a simple procedure, mild reaction conditions, short reaction time, and reusability of the catalyst.     

Highly efficient, one-pot, solvent-free synthesis of 2,4,6-triarylpyridines using a Br?nsted-acidic ionic liquid as reusable catalyst

Abstract  

A simple, efficient, and green method for synthesis of 2,4,6-triarylpyridines by one-pot three-component reaction of acetophenones, aryl aldehydes, and ammonium acetate using 3-methyl-1-(4-sulfonylbutyl)imidazolium hydrogen sulfate [HO₃S(CH₂)₄MIM][HSO₄], a Br?nsted-acidic ionic liquid, as an effective and reusable catalyst under solvent-free conditions is described. This method has several advantages, for example simple procedure with an easy work-up, shorter reaction times, and high yields.     

A one-pot multicomponent reaction for the synthesis of 2-amino-2-chromenes promoted by N,N-dimethylamino-functionalized basic ionic liquid catalysis under solvent-free condition

Abstract  

A simple, clean, and environmentally benign three-component process to the synthesis of 2-amino-4H-chromenes using N,N-dimethylaminoethylbenzyldimethylammonium chloride, [PhCH₂Me₂N⁺CH₂CH₂NMe₂]Cl⁻, as an efficient catalyst under solvent-free condition is described. A wide range of aromatic aldehydes easily undergo condensations with α-naphthol and malononitrile under solvent-free condition to afford the desired products of good purity in excellent yields. Taking into account environmental and economical considerations, the protocol presented here has the merits of environmentally benign, simple operation, convenient work-up and good yields. Furthermore, the catalyst can be easily recovered and reused for at least five cycles without losing its activities.     

Ecofriendly and efficient procedure for hetero-Michael addition reactions with an acidic ionic liquid as catalyst and reaction medium

Abstract  

1-Methylimidazolium trifluoroacetate ([Hmim]TFA) is reported as a cost-effective catalyst for a simple and environmentally benign hetero-Michael reaction. [Hmim]TFA works both as reaction medium and catalyst. The reaction is applicable to various aromatic sulfur and nitrogen nucleophiles. This method has advantages such as high yields, short reaction time, and simple workup. The catalyst could be recycled several times without any loss of activity.     

Zirconium(IV) chloride as versatile catalyst for the expeditious synthesis of quinoxalines and pyrido[2,3-<Emphasis Type="Italic">b</Emphasis>]pyrazines under ambient conditions

Abstract  

Among the various transition metal chlorides, zirconium(IV) chloride was found to be an efficient catalyst for the rapid synthesis of a wide range of 2,3-dialkyl- and 2,3-diaryl-quinoxaline and pyrido[2,3-b]pyrazine derivatives in excellent yields at room temperature. The remarkable features of this catalytic process are the mild reaction conditions, quantitative yields, short reaction times, high conversions, tolerability of various functional groups, clean reaction profiles, and operational simplicity.     

An efficient, high yielding, and eco-friendly method for the synthesis of 14-aryl- or 14-alkyl-14H-dibenzo[a,j]xanthenes using polyvinylsulfonic acid as a recyclable Br?nsted acid catalyst

Abstract  

Aryl or alkyl-14H-dibenzo[a,j]xanthene derivatives were synthesized efficiently by the reaction of 2-naphthol and aromatic or aliphatic aldehydes in the presence of polyvinylsulfonic acid (PVSA) as a reusable Br?nsted acid catalyst under aqueous conditions at 90 °C. This reaction was studied under different conditions, and several solvents were examined. In terms of reaction yield and time, water was found to be the optimum solvent. The catalytic performance of PVSA was then compared with various acidic catalysts under optimized reaction conditions. The catalyst is well characterized using IR and DSC techniques.     

1,3-Dibromo-5,5-dimethylhydantoin as an efficient homogeneous catalyst for synthesis of benzoxazoles, benzimidazoles, and oxazolo[4,5-b]pyridines

Abstract  

A simple and highly efficient method for synthesis of benzoxazoles, benzimidazoles, and oxazolo[4,5-b]pyridines is described. Condensation of orthoesters with o-substituted anilines or 2-amino-3-hydroxypyridine was performed in the presence of catalytic amounts of commercially available, inexpensive, and moisture-stable 1,3-dibromo-5,5-dimethylhydantoin under solvent-free conditions. The corresponding heterocycles were obtained in good to excellent yields. The main advantages of the present procedure are mild reaction conditions, short reaction times, high yields of products, easy work-up, and absence of solvent.     

Granulated copper oxide nanocatalyst: a mild and efficient reusable catalyst for the one-pot synthesis of 4-amino-5-pyrimidinecarbonitriles under aqueous conditions

Abstract  

An efficient method for the synthesis of 4-amino-5-pyrimidinecarbonitriles by the three-component reaction of malononitrile, aldehydes, and N-unsubstituted amidines under aqueous conditions using CuO microspheres as catalyst is reported. The catalyst exhibited remarkable reusable activity.     

One-pot synthesis of 1,2,4,5-tetrasubstituted and 2,4,5-trisubstituted imidazoles by zinc oxide as efficient and reusable catalyst

Abstract  

ZnO is an efficient, readily available, and reusable catalyst for the one-pot synthesis of 1,2,4,5-tetrasubstituted and 2,4,5-trisubstituted imidazoles. This procedure is very simple and affords excellent yields.     

Synthesis of 6-chloroquinolines using benzyltrimethylammonium tetrachloroiodate as a selective chlorinating agent and an efficient generator of HCl

Abstract  

A simple and efficient one-pot synthesis of 6-chloroquinolines was achieved in good yields via the three-component reaction of 2-aminoaryl ketones, α-methylene carbonyl compounds, and BTMA ICl₄ in AcOH.     

A facile and expeditious approach for the synthesis of 2-azetidinone derivatives via a multicomponent reaction

Abstract  

New organic reactions allow chemical transformations which were previously unknown. Therefore, new reactions are important contributions to progress in the field of organic synthesis. Herein, we are reporting a simple, one-pot, efficient three-component synthesis of novel 3-chloro-4-[4-(2-oxo-2H-chromen-4-ylmethoxy)phenyl]-1-phenylazetidin-2-one derivatives using 4-(2-oxo-2H-chromen-4-ylmethoxy)benzaldehydes, anilines, and chloroacetyl chloride in the presence of triethyl amine as a catalyst under different conditions. Taking into account environmental and economic considerations, the protocol presented here has the merits of simple operation, convenient work-up, being environmentally benign, and providing good yields. The synthesized compounds were characterized by IR, ¹H NMR, ¹³C NMR, MS, and elemental analysis.     

A highly efficient and recyclable fluorous palladium catalyst for Heck reactions in water

Abstract  

A fluorous nano-palladium catalyst has been synthesized and characterized. The catalyst is highly active for the Heck reaction of aryl halides with substituted styrenes in water under air. The corresponding Heck products were obtained in high yields with good stereoselectivity (E/Z up to 98:2). In addition, the catalyst could be recovered by fluorous liquid–liquid separation and reused four times without significant loss of activity or stereoselectivity.     

Synthesis of flavanones, azaflavanones, and thioflavanones catalyzed by PMA-SiO2 as a mild, efficient, and reusable catalyst

Abstract  

Cyclization of a variety of chalcones to flavanones catalyzed by 1 mol% phosphomolybdic acid (PMA) supported on silica as a mild, efficient, and reusable catalyst was carried out in high yields. PMA-SiO₂ is an efficient, inexpensive, and green catalyst which gave high conversion yields and could be recycled up to three times without significant loss in activity.