Synthesis and Photocatalytic Properties of Four Coordination Compounds Constructed from Two Benzimidazole-Based Asymmetric Polyazocyclic Ligands

In this paper, two benzimidazole derivative ligands were obtained using o-phenylenediamine and n-pyridine formaldehyde (n = 3, 4) by amine–aldol condensation reactions, which were reacted with selected inorganic metal salts by ambient temperature volatilization method to give compounds 1–4: {[(L1)6]·[Cu8I8]} (1), {[L1]·[CuBr]·H2O} (2), {[L2]·[CuBr]}n (3), and {[(L2)4]·[Cu4I4]} (4). They were characterized by IR, UV-Vis absorption spectroscopy, thermogravimetric analysis, and single crystal X-ray analysis. Simultaneously, compounds 1–4 were found to possess photocatalytic degradation of ciprofloxacin (CIP) by preliminary experimental investigations.