Helical Ribbons of Cadmium( II ) and Zinc( II ) Dicarboxylates with Bipyridyl‐Like Chelates − Syntheses, Crystal Structures and Photoluminescence

Four mixed‐ligand complexes of [M(mpa)(phen)] n [M = Cd ( 1 ) or Zn ( 2 ) and mpa = m ‐phthalate and phen = 1,10‐phenanthroline) and [M 2 (mpa) 2 (2,2′‐bpy) 2 ] n [M = Zn ( 3 ) or Cd ( 4 ) and 2,2′‐bpy = 2,2′‐bipyridine] have been synthesized and their crystal structures have been established by single‐crystal X‐ray diffraction. They all consist of one‐dimensional ribbons featuring dinuclear units. Both 1 and 2 crystallize isomorphously in the monoclinic space group P 2/ c and feature helical chains. While 3 and 4 crystallize in the triclinic space group P $\bar 1$ . The one‐dimensional ribbons are assembled into three‐dimensional networks by π−π stacking interactions. They all show strong blue photoluminescence and are stable in air up to ca. 402, 371, 365 and 370 °C, respectively. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)