Search

Two novel pyrrole-functionalized bis(benzoimidazolium) salts, which are novel NHC-pyrrole-NHC C-N-C Pincer proligands were synthesized in high yield. Both of these compounds are fully characterized by 1H and 13C NMR, IR and elemental analysis. [ABSTRACT FROM AUTHOR]

A series of novel chiral bisimidazolium and chiral bis(benzimidazolium) dichlorides with different substituents were synthesised effectively from the corresponding N-substituted imidazoles or N-substituted benzimidazoles with chiral (S)-2,2'-bis(2-chloroethoxy)-1,1' -binaphthalene in solvent-free conditions at ambient pressure. This protocol features a short reaction time, good yields, an eco-friendly process and easily control and handling. These compounds were fully characterised by NMR, IR and elemental analysis, and their specific rotations were given. [ABSTRACT FROM AUTHOR]

A series of N,N′-diaryl bisimidazolium dichlorides with different alkyl bridged length (n = 2-6, 10) was synthesised from N-arylimidazoles with the less expensive, but less reactive dialkyl chlorides effectively in solvent-free conditions at ambient pressure. Compared with conventional methods, this protocol features a short reaction time, good yields and an eco-friendly process. [ABSTRACT FROM AUTHOR]

An effective intramolecular C–H arylation reaction catalyzed by a bimetallic catalytic system Pd(OAc) 2 /CuI for the synthesis of fluorine-substituted carbazoles from corresponding N -phenyl-2-haloaniline derivatives under ligand free conditions is demonstrated. The established method is effective for both N -phenyl-2-bromoaniline and N -phenyl-2-chloroaniline, and requires the low loading of Pd(OAc) 2 (0.5 mol %). A series of new fluorinated carbazoles were synthesized in excellent yields using the protocol (>83%, 19 examples) and were fully characterized by 1 H, 13 C and 19 F NMR spectral data, HRMS and elemental analysis. All compounds were evaluated for their antibacterial activities against four bacteria ( Bacillus subtilis , Staphylococcus aureus , Escherichia coli and methicillin-resistant S. aureus with resistance to gentamicin) by serial dilution technique. All tested compounds showed antibacterial activity against three test strains ( S. aureus , B. subtilis and MRSA), and most of these compounds displayed pronounced antimicrobial activities against these three strains with low MIC values ranging from 0.39 to 6.25 μg/mL. Among them, compounds 7 and 14 exhibited potent inhibitory activity better than reference drugs meropenem and streptomycin. Three compounds ( 2 , 4 and 5 ) showed antibacterial activity against E. coli . with MIC values from 12.5 to 25 μg/mL. [ABSTRACT FROM AUTHOR]

Highlights: [•] A synthetic method for ultrasmall Pt nanoparticles (∼1nm) is developed. [•] Compared to bulk Pt, structural relaxation is observed in the Pt nanoparticles. [•] The Pt 4f core level energy shifts positively by +1eV compared with bulk Pt. [Copyright &y& Elsevier]

Abstract: Reactions of different alkane-bridged (n =1–3) di-NHC precursors, bisimidazolium chlorides with the NiCl2 in presents of K2CO3 in acetonitrile give the corresponding 16-electron binuclear complexes of the type Ni(di-NHC)(μ-O)2CO in moderate yield. The molecular structures of 1–3 have been determined by X-ray crystallography, which revealed a cis-chelating di-NHC on a slightly distorted square-planar nickel center with κ2-cabonato ligand. The influence of the different di-NHC ligands on the structure and reactivity of the complexes has been studied. The catalytic properties of the complexes were investigated in the Kumada reaction for cross-coupling of phenylmagnesium bromide with a variety of aryl halides. The complex 3 which has the longest linker between two NHCs shows the best catalytic activity in these reactions. [Copyright &y& Elsevier]

The title compounds (III) are efficiently obtained by NHC-catalyzed reaction of 2-aminobenzonitriles (I) with CO2 (II) under mild reaction conditions. [ABSTRACT FROM AUTHOR]