Letters in Organic Chemistry - Volume 11, Issue 10, 2014

A magnetically recoverable heterogeneous catalyst was synthesized by immobilization of Pd on the surface of oleic acid coated Fe3O4 nanoparticle. This catalyst was used for Heck coupling reaction of styrene with various aryl halides in aqueous media. The catalyst /product separation could be easily achieved with external magnetic field.

Perchloric acid immobilized on silica gel (SiO2–HClO4) has been utilized as a mild and cheap reagent for onepot preparation of different varieties of flavylium salts via tandem reaction of different acetophenones with Salicylaldehydes under solvent-free conditions. Different reaction conditions such as conventional heating and microwave irradiation have been investigated. The corresponding flavylium salts have been prepared i Read More

Cyclodextrins (CDs) have been investigated as scaffolds for the construction of anion receptors. Modified α- and β-CDs (1a and 1b, respectively), where hydroxyls on C-2 and C-3 are protected by benzyl groups have been synthesized, and their anion binding properties in CD3CN as an anion receptor were investigated by 1H-NMR titration experiments. CD-based receptors (1a and 1b) effectively bind with AcO- and H2PO4 - by Read More

Several steroid derivatives have been synthesized; however, expensive reagents and special conditions are required. Therefore, in this study two benzamidine-steroid derivative were synthetized using several strategies; the first step was achieved by the synthesis of N-(3-Butyl-1-cyclohexyl-4-cyclohexylimino-azetidin-2-ylidene)-4-nitro-benzamide (4) by the reaction of 4-nitrobenzoyl azide, 1-hexyne and N,N’-Dicyclohexylcarbod Read More

The energies of [π orbitals of the aromatic compounds have been collected to give an index of the aromatic character D where D = {[π1Σ2n(π1-πn)]°/[π1Σ2n(π1-πn)] }× a and n is the number of occupied π orbitals and a is the number of cycles in the molecule. Calculations have been performed on aromatic and heteroaromatic compounds by using DFT method at B3LYP/6-311G+(d,p) level. ERE, HOMA, the molar mag Read More

A new series of functionalized pyrano[2,3-b]quinolines have been prepared in three steps from first condensation of 3-formyl-2-quinolones with Meldrum’s acid, then the corresponding olefins have been alkylated using methyl magnesium iodide, and finally the target compounds have been obtained in good yields after hydrolysis.

An efficient one-pot multicomponent condensation of β-naphthol, aldehydes, and β-oxobenzenepropane (dithioates) is developed using catalytic amount of B3.OEt2 under solvent-free conditions for the synthesis of several 1Hnaphtho[ 2,1-b]pyran derivatives.

The synthesis of three new ruthenium vinylidene complexes I-III with general formula [RuCl2 (=C=CHR)(PCy3)2] (R= p-C6H4CF3 (I), p-C6H4F (II) and C6H9 (III)) has been reported. The vinylidene complexes were isolated as crystalline solids and characterized by 1H, 13C, 19F and 31P NMR, FT-IR spectroscopy, X-ray diffraction and elemental analyses. Due to the electronic repulsion between the chlorines and the steric repulsion Read More

The novel activation model of multifunction thiourea organocatalysts is examined using density functional theory calculations. The key feature of this model is that the two N-H of thiourea group play different roles in activating substrates, one N-H activates cyclohexenone, and the other N-H and tertiary amine of epiquinine activate the hydroxyl of diphenylphosphine oxide together. More importantly, there is a hydrogen bond Read More

A novel 2-(methylthio)benzo[g][1,2,4]triazolo[1,5-a]quinazolin-5(4H)-one was synthesized employing dimethyl N-cyanoimidodithiocarbonate and 3-hydrazinyl-2-naphthoic acid as building blocks. Chemical transformation of the inherent lactam group in the target molecule provided access to a variety of heterocylic derivatives. The obtained compounds are characterized and confirmed by NMR, IR, and HREI-MS analyses.

Eco-friendly, one-pot three-component syntheses of 2-(3H-imidazo[4,5-b]pyridine-2-yl)-N-arylbenzamides have been developed by combining phthalic anhydride with anilines and pyridine-2,3-diamine in water without any catalyst. These reactions involves easy workup, provide good yields and use of water as solvent which were the merits of this preparation.

Heterogeneous palladium catalysts, which are supported by biopolymer, have been applied in water-mediated Heck and the oxidation of alcohols cyclic reaction without assistance of any phosphine ligands. More importantly, owing to the interconversion between the Pd0 and PdII oxidation states during the Heck and oxidation reaction course, the catalyst exhibits good activity in Heck cross-coupling reaction of bromobenzen Read More

A mild and economical method to prepare vildagliptin had been reported with a good yield. In this paper, vildagliptin was synthesized from L-proline and 3-amino-1-adamantanol through chloride acetylation, amination, dehydration and substitution. The total yield of the target compound was 59%.

A green and facile method to synthesize diversified 1,2-disubstituted benzimidazoles has been developed. The total synthesis was performed at room temperature utilizing water and ethanol as solvents. As aqueous media and ethanol have low toxicity and are easily recyclable, the method presented is very suitable for scale-up production. Furthermore, products were obtained in high yield and easily isolated making this met Read More