Increasing structure dimensionality of copper(I) complexes by varying the flexible thioether ligand geometry and counteranions

This work focuses on the systematic investigation of the influences of pyrimidine-based thioether ligand geometries and counteranions on the overall molecular architectures. A N-containing heterocyclic dithioether ligand 2,6-bis( 2-pyrimidinesulfanylmethyl) pyridine (L1) and three structurally related isomeric bis( 2-pyrimidinesulfanylmethyl)benzene (L2-L4) ligands have been prepared. On the basis of the self-assembly of CuX ( X) I, Br, Cl, SCN, or CN) and the four structurally related flexible dithioether ligands, we have synthesized and characterized 10 new metal-organic entities, Cu-4(L1)(2)I-4 1, Cu-4(L1)(2)Br-4 2, [Cu-2(L-2)(2)I-2 center dot CH3CN](n) 3, [Cu(L-3)I](n) 4, [Cu(L-3)Br](n) 5, [Cu(L3)CN](n) 6, [Cu(L4)CN](n) 7, [Cu-2(L-4)I-2](n) 8, [Cu-2(L-4)(SCN)(2)](n) 9, and {[Cu6I5(L4)(3)](BF4), H2O} (n) 10, by elemental analyses, IR spectroscopy, and X-ray crystallography. Single-crystal X-ray analyses show that the 10 Cu( I) complexes possess an increasing dimensionality from 0D ( 1 and 2) to 1D (3-5) to 2D (6-9) to 3D ( 10), which indicates that the ligand geometry takes an essential role in the framework formation of the Cu( I) complexes. The influence of counteranions and d-d weak interactions on the formation and dimensionality of these coordination polymers has also been explored. In addition, the photoluminescence properties of Cu(I) coordination polymers 4-10 in the solid state have been studied.