Reversible Single-Crystal to Single-Crystal Transformation Between Two Copper(II)-Based Two-Dimensional Coordination Polymers for Detection of Fe3+ and 3-Iodobromobenzene

A new two-dimensional copper(II)-based coordination polymer {[Cu(IBA)(2)].2DMF}(n) (Cu-IBA-1.2DMF) was successfully obtained through solvothermal reaction with 4-(1H-imidazol-1-yl)benzoic acid (HIBA) as linker. On exposure to air, Cu-IBA-1.2DMF is slowly converted to a new two-dimensional coordination polymer, namely {[Cu(IBA)(2).H2O].2H(2)O}(n) (Cu-IBA-2.2H(2)O), through a single-crystal to single-crystal (SC-SC) transformation. When suspended in DMF, Cu-IBA-2.2H(2)O regains the initial structure Cu-IBA-1.2DMF, indicating the reversibility of this transformation. Fluorescence spectra measurements show that Cu-IBA-1.2DMF can selectively and sensitively detect Fe3+ and 3-iodobromobenzene.