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A novel and green synthesis of 2-((2-aryl-3-oxoisoindolin-1-yl)methyl)quinazolin-4(3 H )-one is described. The one-pot three-component reaction between 2-methylquinazolin-4(3 H )-ones, aryl amines and 2-formylbenzoic acid, through a sequential condensation, sp 3 C H bond functionalization and cyclization reactions in aqueous media leads to formation of desired compounds in good to excellent yields. [ABSTRACT FROM AUTHOR]

The titled products comprising of two mutually merged bioactive nucleuses, 2-aminobenzo[ d]thiazole and 2,5-dihydropyrrole rings, were obtained from the reaction between dialkyl acetylenedicarboxylates and alkyl 2-(benzo[ d]thiazol-2-yl)amino-2-oxoacetates in the presence of triphenylphosphine at RT. [ABSTRACT FROM AUTHOR]

Abstract: A domino reaction for the rapid and diverse synthesis of spiro[1H-pyrazolo[3,4-b]benzo[h]dihydroquinolin-4,3-indolin-2-ones] is reported. The synthesis represents a thermodynamically-favored four-component reaction between phenylhydrazine, isatins, naphthylamines, and 3-ketoesters giving the novel products in excellent yields under solvent-free conditions. Similar applications of anilines in place of naphthylamines have not led to formation of the expected 4-substituted pyrazolo[3,4-b]quinoline derivatives. The difference was ascribed to lower aromatic character of naphthylamines, with respect to anilines, which enables them to act easier as enamines in reaction with the postulated intermediates formed from condensation of isatins and the in situ generated pyrazolones. Surprisingly, 6-aminouracils in despite of their known enamine properties did not participate in reaction with isatins and pyrazolones, the merit of naphthylamines for this synthesis seems to be met by the favorable balance of their N- and C-nucleophilicity. [Copyright &y& Elsevier]

The ionic liquid [BMIm]BF4 doped with LiBF4 was found to efficiently catalyze the three-component reaction between isocyanides, acetylenic esters and enols or phenols at room temperature, leading to rapid synthesis of 2-aminopyran-annulated systems in fairly high yields. Efficiency of this catalysis and its benefits in terms of improved yields and reaction times could be ascribed to involvement of relatively stable organolithium intermediates which make the reaction more feasible. The ionic solution tolerates a significant amount of dissolved LiBF4, while remaining fluid at room temperature to serve as solvent for the organic substrates. It retains its initial integrity after use and recovery, as it could be recycled several times without appreciable catalytic decrements. The catalytic activity of the ionic composite is completely lost in the absence of LiBF4. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: A novel one-pot three-component reaction of 6-amino-uracil, isatin, and acetophenone was accomplished through a programmed pH variation for the synthesis of 5-(2-oxoindolin-3-yl)-1H-pyrrolo[2,3-d]pyrimidine-2,4(3H,7H)-dione derivatives. The reaction was conducted in a sequential tandem manner to give the oxindole substituted pyrrolo[2,3-d]pyrimidine products in good to excellent yields. Despite of timing all the processes were carried out in one pot. Most of these novel compounds show narrow to good spectrum of antimicrobial activities in vitro. [Copyright &y& Elsevier]

Abstract: Synthesis of spiro[1H-indeno[1,2-b]benzoquinolin-13,3′-indoline]-7,13-dihydro-12,2′-dione derivatives was achieved expediently through three-component reactions between 2H-indene-1,3-dione, 1- or 2-naphthalenamine, and isatin derivatives under catalysis of the ionic liquid N,N,N,N-tetramethylguanidinium triflate. The ionic liquid appeared as a task-specific catalyst solvent being amenable to successive recycling without appreciable decrease in activity. This synthetic method similarly works well when acenaphthylene-1,2-dione or 1H-indene-1,2,3-trione is employed in place of isatin and likewise when 2-aminouracil is used instead of naphthalenamine to furnish the structurally related spirocyclic products. A convergent mechanism was suggested for the reactions to account for the selective formation of the spiro-compounds corresponding to the employed components. [Copyright &y& Elsevier]

An improvement in the rates of Morita-Baylis-Hillman reactions between isatin derivatives and acrylic esters or acrylonitrile under solvent-free conditions is presented. The reactions proceeded expediently at 0 °C under catalysis by 1,4-diazabicyclo[2,2,2]octane (DABCO) to afford the desired adducts. The optimized conditions are indicative of the presence of the more ordered transition states involved in these reactions, supporting the previously suggested mechanism for similar reactions. [ABSTRACT FROM AUTHOR]

An efficient one-pot synthesis of the biologically important spiro[dihydropyridine-oxindole] scaffold was accomplished simply by the reaction of isatin, 2 H-indene-1,3-dione and naphthalen-2-amine in aqueous medium. The scope of this reaction was successfully extended by employing two other reactive ketones (acenaphthylene-1,2-dione and ninhydrin) in place of isatin to access the synthesis of corresponding spirocyclic derivatives. [ABSTRACT FROM AUTHOR]

The use of [bmim]HSO4 renders possible the preparation of the title compounds at ambient temperature via three component reaction between hydroxyquinolinone (I), Meldrum′s acid, and aldehydes. [ABSTRACT FROM AUTHOR]