Abstract
New functional coordination polymers based on the semi-flexible 9,10-di(1H-imidazol-1-yl)-anthracene ligand (L) with ZnII and CdII, namely {[Zn(mu(2)-L)(2)](ClO4)(2)center dot m(MeOH)center dot n(DCM)} n (1), {[Zn(mu(2)-L)(2)] (BF4)(2)center dot m(MeOH)center dot n(DCM)}(n) (2), {[Zn(mu(2)-L)(2)(p-Tos)(2)]center dot m(DCM)center dot n(MeOH)}(n) (3), {[Cd(mu(2)-L)(2)(p-Tos)(2)]center dot m(DCM)}(n) (4) {[Cd(mu(2)-L)(2)(p-Tos)(2)]center dot m(MeOH)center dot(n)(Dioxane)}(n) (5) and {[Zn(mu(2)-L)(2)(CF3CO2)(2)]center dot(2)(Dioxane)}(n) (6), were obtained. Dissolving L in polar solvent mixtures MeOH-DCM (4 : 1) or MeOH-dioxane (1 : 1) with Zn-II and Cd-II salts resulted in the formation of complexes 1, 2, and 5 adopting a cis-conformation of the imidazole groups with respect to anthracene. In less polar mixtures of solvents such as MeOH-DCM (1 : 4) trans-L is observed, leading to the coordination polymers 3-4 with Zn-II and Cd-II. In an intermediate solvent mixture such as MeOH-dioxane (1 : 4), the cis-and trans-conformation coexist as exemplified in complex 6 with Zn-II. In the solid state, complexes 1-5 assemble as supramolecular 2-D coordination polymers with a (4,4) topology, while 6 forms a tridimensional porous network with a cds topology. All compounds reveal strong blue emission in the solid state at room temperature.