Metal to Ligand Interactions and Hydrogen Bonding in the Design of Metallosupramolecular Compounds: Effect of pH and Aprotic Solvents on the Nature of Materials Based on Bis(4-pyridylthio)methane and Copper(II) Chloride

The ligand 4bpytm [4bpytm = bis(4-pyridylthio)methane] in strongly acidic media afforded H24bpytm(NO3)2. The reaction of CuCl2.2H2O with 4bpytm at low pH values afforded three supramolecular compounds: H24bpytm[CuCl4] (1) and the monomeric complexes [CuCl3(H4bpytm)(4bpytm)] (2) and [CuCl2(H4bpytm)2]·Cl2 (3). Nevertheless, the same reaction using aprotic solvents under microwave irradiation afforded the 1D coordination polymers [CuCl2(4bpytm)]·2dmf (4.dmf) and [CuCl2(4bpytm)]·2dmso (4.dmso). The 3D supramolecular organization through weak interactions has been analyzed for all of the compounds, and their thermal behavior and structural dynamics after solvent release were also investigated for 4.dmf and 4.dmso. X-ray structural analysis of these complexes showed that the synthetic conditions used represent an effective method to obtain metal−organic square grid networks with cavities.