RESUMO
Phosphine gold(I) aryl acetylide complexes equipped with a central bis(urea) moiety form 1D hydrogen-bonded polymeric assemblies in solution that do not display any optical activity. Chiral co-assemblies are formed by simple addition of an enantiopure (metal-free) complementary monomer. Although exhibiting an intrinsically achiral linear geometry, the gold(I) aryl acetylide fragment is located in the chiral environment displayed by the hydrogen-bonded co-assemblies, as demonstrated by induced circular dichroism (ICD).
Assuntos
Ouro/química , Compostos Organometálicos/síntese química , Fosfinas/química , Ureia/química , Dicroísmo Circular , Ligação de Hidrogênio , Compostos Organometálicos/químicaRESUMO
A novel class of chiral luminescent square-planar platinum complexes with a π-bonded chiral thioquinonoid ligand is described. Remarkably the presence of this chiral organometallic ligand controls the aggregation of this square planar luminophor and imposes a homo- or hetero-chiral arrangement at the supramolecular level, displaying non-covalent Pt-Pt and π-π interactions. Interestingly these complexes are highly luminescent in the crystalline state and their photophysical properties can be traced to their aggregation in the solid state. A TD-DFT calculation is obtained to rationalize this unique behavior.
RESUMO
A new series of monoselenoquinone and diselenoquinone πâ complexes, [(η(6) -p-cymene)Ru(η(4) -C6 R4 SeE)] (R=H, E=Se (6); R=CH3 , E=Se (7); R=H, E=O (8)), as well as selenolate πâ complexes [(η(6) -p-cymene)Ru(η(5) -C6 H3 R2 Se)][SbF6 ] (R=H (9); R=CH3 (10)), stabilized by arene ruthenium moieties were prepared in good yields through nucleophilic substitution reactions from dichlorinated-arene and hydroxymonochlorinated-arene ruthenium complexes [(η(6) -p-cymene)Ru(C6 R4 XCl)][SbF6 ]2 (R=H, X=Cl (1); R=CH3 , X=Cl (2); R=H, X=OH (3)) as well as the monochlorinated πâ complexes [(η(6) -p-cymene)Ru(η(5) -C6 H3 R2 Cl)][SbF6 ]2 (R=H (4); R=CH3 (5)). The X-ray crystallographic structures of two of the compounds, [(η(6) -p-cymene)Ru(η(4) -C6 Me4 Se2 )] (7) and [(η(6) -p-cymene)Ru(η(4) -C6 H4 SeO)] (8), were determined. The structures confirm the identity of the target compounds and ascertain the coordination mode of these unprecedented ruthenium πâ complexes of selenoquinones. Furthermore, these new compounds display relevant cytotoxic properties towards human ovarian cancer cells.
Assuntos
Antineoplásicos/química , Antineoplásicos/síntese química , Complexos de Coordenação/química , Complexos de Coordenação/síntese química , Citotoxinas/química , Quinonas/química , Quinonas/síntese química , Rutênio/química , Linhagem Celular Tumoral , Cristalografia por Raios X , Feminino , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Neoplasias Ovarianas/tratamento farmacológicoRESUMO
Heterobimetallic (di)benzoindenyl Re-Cr complexes have been prepared by a sequence starting from (8-bromobenzo[e]-indenyl)potassium. Reaction with pentacarbonylrhenium bromide affords tricarbonylrhenium complex 2, which has been modified to rhenium-chromium carbene complex 3. Its chromium-templated [3 + 2 + 1]benzannulation afforded the anti(Cr(CO)(3)-Re(CO)(3)) dibenzoindenyl complex 4 as the major product along with the syn diastereoisomer 5. The molecular structures of all heterobimetallic complexes were established by X-ray analyses.