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Electrocatalytic multicomponent transformation of 6-aminouracils, aromatic aldehydes and malononitrile in ethanol in an undivided cell in the presence of potassium bromide as an electrolyte leads to 7-amino-pyrido[2,3- d]pyrimidine-6-carbonitrile derivatives in short reaction times (8-20 min) and good to high yields (70-86%).

11-(1H-Pyrrol-1-yl)-11H-indenol[1,2-b]quinoxaline and 3-(1H-pyrrol-1-yl)indolin-2-one derivatives are synthesized in good yields in a novel, one-pot, and efficient process by condensation of 11H-indenol[1,2-b]quinoxalin-11-one or isatin derivatives with 4-hydroxyproline on solid-support montmorillonite K10 under microwave irradiation.

A strategy of efficient and convenient green synthesis for the preparation of tetrahydroisoquinolonic acids in three-component cyclocondensation reaction of homophthalic anhydride, aldehydes, and amines using the inexpensive, nontoxic, and easily available KAl(SO4)2.12H2O catalyst is described. This reaction is stereoselective in the preparation of cis-isoquinolonic acids.

Quinoxaline derivatives are compounds with pharmaceutical applications. In this study, derivatives of N1-(11H-indeno[1,2-b]quinoxalin-11-ylidene)benzene-1,4-diamine were synthesized and attached to carboxylated multi-wall nanotubes (MWNT-COOH). Functionalized carbon nanotubes were characterized by scanning electron microscopy (SEM) to study the shape of structures, transmission electron microscopy (TEM), fast Fourier transform infrared (FT-IR), Raman spectroscopy, and elemental analysis. [ABSTRACT FROM AUTHOR]

We found that elemental iodine and bromine are converted to trihalide nucleophiles (triiodine and tribromide anion, respectively) in the presence of catalytic amounts of meso-tetraphenylporphyrins (H2TPP). Therefore a highly regioselective method for the synthesis of β-haloalcohols through direct ring opening of epoxides with elemental iodine and bromine in the presence of H2TPPs as new catalysts is described. At room temperature a series of epoxide derivatives were converted into the corresponding halohydrins resulting from an attack of trihalide species anion atoms at the less substituted carbon atom. This method occurs under neutral and mild conditions with high yields in various aprotic solvents, even when sensitive functional groups are present. [ABSTRACT FROM AUTHOR]

Abstract: 3,4-Dihydropyrimidin-2(1H)-ones derivatives were synthesized in moderate to high yields in one-pot three component reaction from the corresponding aldehydes, ketones or 1,3-dicarbonyl compounds and urea, in the presence of catalytic amount of KAl(SO4)2·12H2O (Alum) supported on silica gel (Alum-SiO2) as a non-toxic, reusable, inexpensive and easily available reagent, under solvent-free conditions at 80°C. Compared to the classical Biginelli reaction, this new method consistently has the advantage of good yields. [Copyright &y& Elsevier]

KAl(SO4)2·12H2O is found to catalyze efficiently the stereoselective one-pot three-component cyclocondensation of homophthalic anhydride, aldehydes, and amines under mild conditions to afford the corresponding cis-isoquinolonic acids in good yields. [ABSTRACT FROM AUTHOR]