Five Ag(I) complexes containing the ligands bis(imidazol-2-yl)methane (2-BIM) and its derivatives were prepared and [Ag 2 (2-BIM) 2 ](ClO 4 ) 2 and [Ag 2 (2-BIM(Bz)OH) 2 ](ClO 4 ) 2 Á EtOH were characterised using X-ray crystallography. In each dimer the two Ag(I) ions are two-coordinate and there are small but definite argentophilic Ag-Ag (d 10 -d 10 ) interactions. All of the complexes display anti-fungal activity when tested in vitro against the fungal pathogen Candida albicans.
Cu(II) and Zn(II) complexes of N-hydroxyimidazoles were synthesised by reacting simple metal perchlorate salts with the imidazole ligand in alcohol and formulated with a metal:ligand ratio of 1:2. The X-ray crystal structures of five complexes (four Cu(II) and one Zn(II)) were obtained and each showed the two trans, N-hydroxyimidazole ligands forming six-membered, chelate rings with the metal. Both of the NO chelating, neutral N-hydroxyimidazole ligands are in the zwitterion form, with the uncoordinated imidazole imine N atom being protonated and the oxime O atom deprotonated. In the solid state the complexes form hydrogen-bonded supramolecular structures.
The steric and electronic requirements have been investigated for the synthesis of 2,3‐dihydro‐4(1H)‐quinolinones by the tandem Michael‐SNAr reaction. Substrates bearing a single methyl group at the β‐enone carbon gave excellent yields of the title compounds from both the E and Z isomers with X═H or NO2. Substrates with β,β‐dimethyl substitution at the Michael terminus gave low yields of heterocyclic products in molecules having monoactivated SNAr aromatic acceptor rings (X═H) and very good yields for diactivated systems (X═NO2). For these hindered substrates, success in the final cyclization hinges on the ability of the aromatic acceptor to capture the pendant nitrogen nucleophile of the initial Michael adduct before this intermediate can revert to starting materials.
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