The synthesis of trifluoromethyl-substituted pyridylboronic acids and pyrazolylboronic esters is described via lithiation-boronation protocols (Schemes 1, 3 and 4). A study of their palladium-catalysed cross-couplings with heteroaryl halides is presented. CF3-substituted aryl/heteroaryl-pyridines are thereby obtained (51-98% yields). Analogous cross-couplings have yielded heteroaryl-3-(trifluor...

Abstract A method for the synthesis of functionalized piperidines containing 3 contiguous stereocentres in 2-,3- and 4- positions uses a diastereoselective nitro-Mannich to control stereochemistry. The reaction between β-aryl/heteroaryl substituted nitroalkanes glyoxylate imine provides β-nitro-amines with good selectivity (70:30 >95:5) syn, anti-diastereoisomers. Reductive cyclisation BF3.OEt2...

a simple, fast, efficient and environmentally friendly method for synthesis of benzimidazole and its 2-alkyl, aryl and heteroaryl substituted derivatives was developed using zeolite hy. two component cyclolcondensation of 1,2-phenylenediamine (o-phenylenediamine) and commercially available carboxylic acids catalyzed by zeolite hy without any solvent, under microwave irradiation led to formation...

We report the synthesis of l '-heteroaryl-2,S-d imethylazaferrocenes (heteroaryl = 2-bromothiophen-S-yl and 2-bromopyrid-6-yl) via palladium ca talysed cross-coupling reactions along with their crysta llographically determined structures. The newly synthesized compounds as well as the parent 2,S-dimethylazaferrocene have been investigated by cycl ic voltammetlY (CV) and were found to exhibit re...

A palladium-catalyzed aerobic and ligand-free Suzuki reaction in aqueous ethanol has been developed for the synthesis of N-heteroaryl substituted 9-arylcarbazolyl derivatives. A number of N-heteroaryl halides, namely 2-halogenated pyridines, 2-bromoquinoline, 5-bromopyrimidine and 2-chloropyrazine, were coupled with 4-(9H-carbazol-9-yl)phenylboronic acid (CPBA) or 9-phenyl-9H-carbazol-3-ylboron...

Differently substituted pyridinium N-heteroarylaminides have been prepared in one step with good yield from N-aminopyridinium iodide and the corresponding heteroaryl chloride. q 2003 Elsevier Ltd. All rights reserved. For many years conjugated heterocyclic N-ylides, a subgroup of mesomeric betaines, have been widely used as building blocks for the synthesis of fused heterocyclic systems and nat...

We report the Pd-catalyzed α-arylation of α,α-difluoroketones with aryl and heteroaryl bromides and chlorides catalyzed by an air- and moisture-stable palladacyclic complex containing P(t-Bu)Cy2 as ligand. The combination of this Pd-catalyzed arylation and base-induced cleavage of the acyl-aryl C-C bond within the α-aryl-α,α-difluoroketone constitutes a one-pot, two-step procedure to synthesize...

A versatile method for the preparation of N-heteroaryl substituted aminoacid derivatives is suggested. The method avoids facile diketopiperazine formation.

Aryl and heteroaryl derivatives with an alkylaminoethyl chain on the hydroxyl group of the benzene ring are prepared and evaluated against Mycobacterium tuberculosis H37Rv and showed the activity in the range of 3.12-25 μg/mL. The compounds containing alkylaminoethyl chains on aryl-chromeneyl carbinol do not show good activity. Similarly compounds with bis and tris-alkylaminoethyl chains on ary...