The d10 metal-sulfosalicylate complexes: Herring-bone, ladder and double-stranded chain frameworks with green luminescences

Assembly of 5-sulfosalicylic acid (H3L) and d10 transition metal ions (CdII, AgI) with the neutral N-donor ligands produces five new complexes: [Cd2(HL)2(4,4′-bipy)3]n·2nH2O (1), {[Cd2(μ2-HCO2)2(4,4′-bipy)2(H2O)4][Cd(HL)2(4,4′-bipy)(H2O)2]}n (2), {[Cd(4,4′-bipy)(H2O)4][HL]·H2O}n (3), [Cd(HL)(dpp)2(H2O)]n·4nH2O (4), {[Ag(4,4′-bipy)][Hhbs]}n (5) (4,4′-bipy=4,4′-bipyridine, dpp=1,3-di(pyridin-4-yl)propane, H2hbs=4-hydroxybenzenesulfonic acid, the decarboxylation product of H3L). Complex 1 adopts a 5-connected 3D bilayer topology. Complex 2 has the herring-bone and ladder chain, which are extended to a 3D network via hydrogen bonding. In 3–4 complexes, 3 is a 3D supermolecular structure formed by polymeric chains and 2D network of HL2−, while 4 gives the double-stranded chains. In 5, ladder arrays are stacked with the 2D networks of Hhbs− anions in an –ABAB– sequence. Complexes 1–4 display green luminescences in solid state at room temperature, while emission spectra of 3 and 4 show obvious blue-shifts at low temperature.

Graphical abstractReactions of 5-sulfosalicylic acid (H3L) and d10 metal ions (CdII, AgI) produce five new complexes. Complexes 1–4 all display green luminescences at room temperature.Figure optionsDownload full-size imageDownload as PowerPoint slide