Syntheses, structures, and properties of nine d10or p-block coordination polymers based on a ligand containing both terpyridyl and sulfo groups

Abstract

Nine new coordination compounds, namely, {[Zn(HDSPTP)2(H2O)4]·6H2O}n (H2DSPTP = 4′-(2,4-disulfophenyl)-4,2′:6′,4′′-terpyridine, (1), [Cd(DSPTP)(H2O)2]n (2), {[Ag(HDSPTP)]·30H2O}n (3), {[Ag(HDSPTP)(H2O)]·3H2O}n (4), [Ag2(DSPTP)]n (5), {[Ag4(DSPTP)2(H2O)3]·2H2O}n (6), [Pb(DSPTP)(H2O)2]n (7), {[Pb(DSPTP)(H2O)3]·3H2O}n (8), and [PbK(DSPTP)(NO3)(H2O)2]·H2O}n (9), were synthesized by introducing a ligand with both terpyridyl and sulfo groups as organic linkers. The reaction of H2DSPTP with Zn(II) salts only resulted in a mononuclear complex (compound 1), in which most donor groups appear uncoordinated, whereas the reaction with Cd(II) salts under similar conditions resulted in a three-dimensional (3D) twofold interpenetrated dia framework (compound 2). The reactions of H2DSPTP with AgCF3CO2 or AgNO3 resulted in compounds 3–6 with different structures: a porous supramolecular framework via interlaced packing of one-dimensional (1D) coordination chains (compound 3), a two-dimensional (6,3) network based on coordination bonds and Ag⋯O interactions (compound 4), a 3D framework based on 1D [Ag2(2-SO3−)2]n secondary building blocks (compound 5), and a twofold interpenetrated framework with a binodal (4,6)-connected fsh topology based on planar tetranuclear SBUs as nodes (compound 6). The reactions of H2DSPTP with Pb(NO3)2 resulted in the following three compounds: a 3D twofold interpenetrated dia framework (complex 7), a twofold interpenetrated (6,3) network (compound 8), and a 3D complicated framework based on tetranuclear SBUs, double-bridge DSPTP2− ligands, and [K(H2O)]+ species (compound 9). The structural diversity is mainly attributed to the rich coordination behaviors of the HDSPTP−/DSPTP2− ligands and the metal center and can be controllably synthesized by altering the metal to ligand ratio, added alkali, and the pH value for the Ag(I) and Pb(II) compounds. Compound 2 exhibits a high thermal stability above 500 °C, undergoes a crystalline–amorphous–crystalline phase transition as temperature is increased from 25 °C to 500 °C, and shows an amorphous–crystalline phase transition when rehydrated. Moreover, the luminescence properties of all the compounds were also investigated.