One-pot three-component green synthesis of novel dihydrophthalazine-1,4-diones

Green and efficient one-pot three-component synthesis of novel 2-(7-amino-2,2-dimethyl-4-oxo-5-phenyl-4,5-dihydropyrano[2,3-d][1,3]dioxin-6-ylcarbonyl)-2,3-dihydrophthalazine-1,4-diones have been developed by condensing 3-(1,4-dioxo-1,2,3,4-tetrahydrophthalazin-2-yl)-3-oxopropanenitrile with benzaldehydes and Meldrum’s acid using L-proline as catalyst in ethanol at room temperature. The products have been isolated as pure compounds in good yields without using column chromatography.     

One-pot synthesis of monosubstituted aryl(hetaryl)acetylenes by direct introduction of the CCH residue into arenes and hetarenes

A convenient one-pot synthesis of aryl(hetaryl)acetylenes by cross-coupling of aryl(hetaryl)iodides with acetylene in presence of PdCl₂(Ph₃)₂, CuI and K₂CO₃ in DMF has been developed.     

One-pot and catalyst-free synthesis of thiosemicarbazones via multicomponent coupling reactions

A novel and efficient procedure for the synthesis of thiosemicarbazones has been achieved via a multicomponent and catalyst-free reaction of phenyl or p-chlorophenyl isothiocyanate, hydrazine, and aldehydes or ketones. The method afforded 20 thiosemicarbazones in good yields and short reaction time.     

A stereoselective synthesis of spiro-dioxolanes via the multicomponent reaction of dicarbomethoxycarbene, aldehydes and 1,2- or 1,4-diones

The three component reaction of acyclic carbonyl ylides generated from dicarbomethoxycarbene and aldehydes with 1,2- and 1,4-diones is described. The reaction afforded the corresponding spiro-dioxolanes in good yields.     

Synthesis and structure of aryl(hetaryl)spiropyrrolidones

Hydrogenation of the diastereouniform 3-[1-aryl(hetaryl)-2-nitroethyl]-3-methoxycarb-onyl-4-phenyl(3-pyridyl)-2-pyrrolidones is accompanied by intramolecular acylation of the formed amino group to afford the diastereomerically pure 4,4′-aryl(hetaryl)-3,3′-spirobi-[2-pyrrolidones]. The structures of these diastereomers were characterized by IR, ¹H and ¹³C NMR spectroscopy using heteronuclear correlation experiments, and X-ray diffraction study.     

One-pot multicomponent synthesis of polysubstituted indolizines

Concise and efficient four-component tandem approaches to polysubstituted indolizines have been developed under metal-free and mild aerobic conditions in refluxing acetonitrile. The mechanism of the novel reactions was proposed involving the formation of pyridinium ylides and α,β-unsaturated ketones with subsequent 1,3-dipolar cycloaddition and aromatization reaction.     

One-pot synthesis of substituted indolines via a copper-catalyzed sequential multicomponent/C-N coupling reaction

One-pot synthesis of 2-(N-sulfonylimino)indolines has been developed. The procedure combines the copper-catalyzed three-component reaction of sulfonyl azides, o-bromophenylacetylenes, and amines and the copper-catalyzed intramolecular C-N coupling in one sequence, which afforded the products in moderate to good yields. The resulting 2-(N-sulfonylimino)indolines could be easily transformed to pharmaceutically valuable oxindoles (indolin-2-ones).     

One-pot synthesis of aryl biaryl sulfones

Synthesis of aryl biaryl sulfones 3 with good yields is described. The one-pot efficient synthetic route is carried by the NaH-mediated tandem [C3+C3] annulations of cinnamaldehydes 1 and propargylic sulfones 2 under the boiling THF conditions.     

One-pot synthesis of disulfide-linked N-sulfonylazetidin-2-imines via a copper-catalyzed multicomponent cascade reaction

A copper-catalyzed, three-component reaction between a sulfonyl azide, an alkyne, and a 2-aminothiophenol derived Schiff base is reported. This novel one-pot procedure involves a click reaction, a formal [2+2] cycloaddition, and S–S coupling, therefore, providing a unique method for the synthesis of novel disulfide-linked N-sulfonylazetidin-2-imines under mild conditions.     

One-pot synthesis of benzo[f]indole-4,9-diones from 1,4-naphthoquinones and terminal acetylenes

In this paper, a concise one-pot method for the construction of benzo[f]indole-4,9-dione motifs is described. These transformations proceed via a sequential palladium- and copper-catalyzed coupling reaction of 1,4-naphthoquinones with terminal acetylenes, followed by a copper-catalyzed intramolecular cyclization reaction of the resulting coupling product.     

Synthesis and structure of N-substituted aryl(hetaryl)spiropyrrolidones

4,4′-Diaryl-3,3′-spirobi[2-pyrrolidones] were synthesized by hydrogenation of N-substituted 3-methoxycarbonyl-3-(2-nitro-1-arylethyl)-4-phenyl-2-pyrrolidones followed by intramolecular heterocyclization. Structure of the compounds obtained was determined by IR, ¹H, and COSY NMR spectroscopy.     

Cu-catalyzed one-pot multicomponent approach for the synthesis of symmetric and asymmetric 1,4-dihydropyridine (1,4-DHP) linked 1,2,3-triazole derivatives

Abstract

Synthesis of various symmetric and asymmetric 1,4-DHP linked 1,2,3-triazole derivatives from economical and readily available starting materials via a convenient methodology in a single-pot method using CuSO₄·5H₂O as an efficient catalyst has been reported. The reaction proceeded efficiently under the optimized reaction conditions with excellent functional group compatibility providing the desired products in good yields. The method appears to be an efficient combinatorial strategy for the synthesis of new 1,4-DHP linked triazole derivatives.     

One-pot synthesis of iodine-substituted 1,4-oxazepines

A facile one-pot method for the synthesis of iodine-substituted 1,4-oxazepines is reported. When reacted with ZnCl₂ and I₂ in DCM at 40?°C, N-propargylic β-enaminones, prepared by the conjugate addition of propargylamine to α,β-alkynic ketones, underwent 7-exo-dig cyclization by zinc chloride and concomitant reaction with molecular iodine to afford 2-(iodomethylene)-2,3-dihydro-1,4-oxazepines in good to high yields. This cyclization was found to occur with broad scope of substrates and high tolerance of functional groups. The resulting iodine-containing 1,4-oxazepines can be further elaborated to more complex structures by subsequent cross-coupling reactions, which may provide a platform for biological studies.     

One-pot synthesis of pyranocoumarins via microwave-assisted pseudo multicomponent reactions and their molecular switching properties

Two new pyranocoumarins were synthesized via one-pot, microwave-assisted pseudo multicomponent condensations of coumarin and 4-methylquinoline to investigate their molecular switching properties. Both are light-sensitive and have a distinct change of color upon UV irradiation. The reaction can be reverted by treating the photogenerated products with imidazoline-functionalized magnetic nanoparticles, which can be swiftly recycled with an external permanent magnet.     

Synthesis and structure of 3-{[aryl (hetaryl)amino]methylene}chromane-2,4-diones and their metal complexes

3-{[Aryl(hetaryl)amino]methylene}chromane-2,4-diones (HL) were synthesized and used for chemical and electrochemical synthesis of Cu(II), Ni(II), and Co(II) complexes of the general formula ML2, as well as the ZnLOOCCH3 complex. The structure of the complexes was studied by IR, ¹Н NMR, and X-ray absorption spectroscopy. Density functional theory (DFT) calculations showed that the energetically most favored form of compounds HL is an aminoketone tautomeric form. The crystal structure of the solvate of bis-{3-[(4-methylanilinato)methylene]chromane-2,4-dionato}copper(II) with two DMF molecules was determined by X-ray diffraction analysis.     

One-pot synthesis of tricyclo-1,4-benzoxazines via visible-light photoredox catalysis in continuous flow

A facile one-pot synthesis of tricyclo-1,4-benzoxazines has been developed via metal-free intramolecular cyclization of indole derivates. These reactions were efficiently achieved at ambient temperature by using visible-light photoredox catalysis in continuous flow. This directed intramolecular cyclization could be easily handled and scaled up in an open flask, enabling construction of a focused compound library for further pharmacological evaluation.     

One-pot synthesis of diaryl ketones from aldehydes via palladium-catalyzed reaction with aryl boronic acids

A Pd-catalyzed coupling-type reaction of aldehydes and organoboronic acids was achieved in the presence of P(1-nap)₃, using Cs₂CO₃ in toluene, providing diaryl ketones with yields ranged from moderate to excellent. The efficiency of this reaction was demonstrated by the compatibility with nitro, cyano, trifluoromethyl, fluoro and chloro groups. Moreover, the rigorous exclusion of air/moisture is not required in these transformations.     

One-pot synthesis of α-aminonitriles from alkyl and aryl cyanides: a Strecker reaction via aldimine alanes

A one-pot Strecker reaction using various alkyl, arylalkyl and arylnitriles is developed. Aldimine alanes were generated in situ from nitriles by the addition of diisobutylaluminium hydride, and were converted into the corresponding imines on reaction with (S)-(−)-1-phenylethylamine. Nucleophilic addition to the imines in the presence of catalytic triethylamine, using acetone cyanohydrin as a cyanide source, provided α-aminonitriles.     

One-pot multicomponent synthesis of novel thiazol-2-imines via microwave irradiation and their antifungal evaluation

Microwave-assisted green approach is developed for an efficient synthesis of thiazol-2-imines under catalyst-free conditions. The desired products are formed by one-pot three-component reaction which is an improvised method for Hantzsch thiazole synthesis. The microwave-assisted protocol gives excellent yields with high purity in just 10–15?min. All the synthesized compounds have been screened for antifungal activity and some of the derivatives show a broad spectrum against fungal pathogens.