Anion-Controlled Assembly of Silver(I) Complexes of Multiring Heterocyclic Ligands: A Structural and Photophysical Study

Four multiring heterocyclic ligands with benzimidazole (L1 and L3) and benzothiazole nuclei (L2 and L4) are reported. Their silver(I) complexes involving a variety of anions (both organic and inorganic) have been prepared by the process of self-assembly and structurally characterized by single-crystal X-ray diffraction analyses. Discrete metallocyclic complexes [Ag(L3)(X)]2 (X = NO3−, 3a; cis-HOOCCH═CHCOO−, 3b; 0.5SiF62-, 3c) and [Ag(L4)(Y)]2 (Y = NO3−, 4a; CF3SO3−, 4b) have been formed with the ligands L3 and L4, respectively, where the pyridine nitrogen atom N1 is in the 3-position as against the coordination polymers [Ag(L1)(H2O)(NO3)]n, 1a, [Ag(L1)(CF3COO)]n, 1b and {2[Ag(L2)2(ClO4)].0.5.C2H5OH}n 2a, and [Ag(L2)2(cis-HOOCCH═CHCOO)]n, 2b, with the ligands L1 and L2, respectively, in which the N1 atom occupies the 4-position in the pyridine ring. In addition to the primary ligands (L1−L4), the counteranions also have a dominant influence on the overall structures of these compounds. Secondary bonding in...