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A novel synthetic procedure has been designed for the synthesis of imidazo-based and benzimidazo-based privileged templates on s-triazine nucleus through a phenoxyl spacer by exploiting the versatility of the reactive synthon imidate ester. [ABSTRACT FROM AUTHOR]

A novel homologous series of N-[4-[4′-n-alkoxy)benzoyloxy-2-hydroxybenzylidene)-4-carbethoxy anilines, H2n+1CnOC6H4C(O)OC6H3(OH)C(H)˭NC6H4COOC2H5(n = 6, 8, 10, 12, 14, 16) and their copper(II) complexes have been synthesized. All these compounds have been characterized by suitable spectroscopic techniques. The mesomorphic properties of these compounds were investigated by differential scanning calorimetry (DSC) and polarizing optical microscopy (POM). The ligands exhibit wide range of enantiotropic smectic A and nematic phases as confirmed by their typical optical texture under polarizing microscope. The square planar copper(II) complexes of the ligands show only an isotropic phase at higher temperature and no mesogenic nature is observed. DFT calculations have been performed using GAUSSIAN-03 program at B3LYP level to obtain the stable electronic structure of the ligand with decyloxy chain length and its copper(II) complex. [ABSTRACT FROM AUTHOR]

The titled azoester liquid crystalline homologous series consists of eleven homologues. The pentyl to tetradecyl derivatives of the series are nematogenic without exhibition of smectogenic character. Rest of the members of the series are nonliquid crystalline in nature. Textures of the nematic mesophase are schlieren or threaded type. Transition curves in the phase diagram showed normal phase behavior. Transition temperatures and liquid crystal behavior observed under an optical polarizing microscope equipped with a heating stage. An odd even effect is observed for nematic-isotropic transition curve. Analytical and spectral data confirms the structures of the molecules. Present homologous series is predominant nematogenic and partly nonmesogenic. Average thermal stability for nematic is 125.33°C and nematogenic mesophase length varies between 12°C to 48°C at tetradecyl (C14) and octyl (C8) derivatives, respectively. [ABSTRACT FROM AUTHOR]

A heterogeneous catalyst, copper(II) on 4 Å molecular sieves has successfully been used in the arylation of ethyl acetoacetate, selectively forming arylacetic esters in high yields. The air stable and easily handled catalyst can be simply filtered off during purification thus avoiding significant metal contamination of the product. [ABSTRACT FROM AUTHOR]

A one-pot, convergent method for the synthesis of 5,6-dihydroquinolines by simple mixing of two equivalents of acyclic α,α-dicyanoolefins and one equivalent of acetylenic ester in the presence of Et 3 N is described. Three new C–C and one C–N bonds are created in this operation. In the same reaction, cyclic α,α-dicyanoolefins led to the formation of succinates. Further hydrolysis and decarboxylation of 5,6-dihydroquinoline led to quinoline. [ABSTRACT FROM AUTHOR]

A sequential procedure for the synthesis of 2,5-disubstituted thiazoles from terminal alkynes, sulfonyl azides, and thionoesters is reported. A copper(I)-catalyzed 1,3-dipolar cycloaddition of terminal alkynes with sulfonyl azides affords 1-sulfonyl-1,2,3-triazoles, which then react with thionoesters in the presence of a rhodium(II) catalyst. The resulting 3-sulfonyl-4-thiazolines subsequently aromatize into the corresponding 2,5-disubstituted thiazoles by elimination of the sulfonyl group. [ABSTRACT FROM AUTHOR]

Highly practical synthetic methods were developed for the C- and N-selective Grignard addition reactions of N-4-MeOC6H4-protected a-aldimino esters in the presence or absence of zinc(II) chloride. Diastereoselective C-alkyl addition, tandem C-alkyl addition-N-alkylation, and some transformations to synthetically useful optically active azacycles were demonstrated. [ABSTRACT FROM AUTHOR]

Cell-permeating esters of 2-ketoglutarate (2-KG) have been synthesized through a convergent sequence from two modules in two and three steps, respectively. This route provides access to a full series of mono- and disubstituted 2-KG esters, enabling us to define the effect of regioisomeric masking on metabolite release and antihypoxic activity in cell-based assays. In addition to providing insight into the biological activity of cell permeable 2-KG esters, the straightforward and modular nature of this synthetic route may prove useful for the development of next-generation 2-KG analogues for diagnostic and therapeutic applications. [ABSTRACT FROM AUTHOR]

A series of 1,2,4-triazole-3-carboxamides have been prepared from 1,2,4-triazole-3-carboxylates under mild conditions. Efficient synthesis of amides directly from esters and amines is achieved under mild, neutral conditions with liberation of alcohol as by-product. Both primary and secondary aliphatic and aromatic amines can be utilized. This unprecedented, general, environmentally benign reaction proceeds in toluene under microwave conditions. The newly synthesized compounds were characterized by spectral and elemental analyses. [ABSTRACT FROM AUTHOR]

Multicomponent self-assembly of Re2(CO)10, diaryl dichalcogenide ligands (REER), andphenyl-1,3,5-tris(isonicotinate)(ptin) under solvothermal conditions has resulted in the formationof chalcogen-bridged trigonal metallaprisms of the general formula[{(CO)3Re(μ-ER)2Re(CO)3}3(μ3-ptin)2] (1–5), wherein E = S, Se and R = phenyl, p-tolyl,benzyl. Oxidative addition of diaryl disulfide/diaryl diselenide toRe2(CO)10with the ester-functionalized tritopiclinker ptin has yielded trigonal metallaprisms 1–5under facile reaction conditions. The metallaprisms 1–5have been characterized using elementalanalysis and IR, UV–vis, and NMR spectroscopic techniques.Single-crystal X-ray structures have been obtained for 3and 4. The structural features and chirality of metallaprisms 3and 4in the solid state have been highlighted. [ABSTRACT FROM AUTHOR]

Cross-coupling reactions of chloroformates with organocopper reagents, derived from Grignard reagents, cuprous bromide and lithium bromide, provide a rapid and straightforward method for the synthesis of esters. [ABSTRACT FROM AUTHOR]

Reaction of morpholine with iBu2AlH generates diisobutyl(morpholino)aluminum which can be easily trapped with a variety of esters to give the corresponding amides (III). [ABSTRACT FROM AUTHOR]

The reaction of aryldiazoacetates (I) with copper trifluoromethylthiolate (II) affords desired α-(trifluoromethylthio)esters (III). [ABSTRACT FROM AUTHOR]