Syntheses, crystal structures and properties of six coordination compounds with flexible dps ligand

Six new compounds: [M(dps)(dca)2]∞ (1, M = Cd; 2, M = Fe), [Cu(dps)(dca)2(CH3OH)2]∞ (3), [M(dps)2(SCN)2(H2O)2]∞ (4, M = Cd; 5, M = Fe), [Cu(dps)4(SCN)2]∞ (6), (dps = 4,4′-dipyridyl sulfide, dca = dicyanamide) were synthesized, characterized by FT-IR, element analysis and TG. Their structures were determined by single crystal X-ray diffraction. According to the structure analysis, compounds 1 and 2 are three-dimensional microporous frameworks constructed by Cu–dps–Cu and Cu–dca–Cu bridges; compound 3 shows a zigzag chain constructed by a Cu–dps–Cu bridge; compounds 4 and 5 show double-stranded chains constructed by a Cu–(dps)2–Cu bridge while thiocyanate anions act as terminal groups; compound 6 is a mononuclear compound. Moreover, compound 1 shows visible yellow luminescence under UV light irradiation and such phenomenon is mainly attributed to inter-ligand transitions.

As a flexible ligand, 4,4′-dipyridyl sulfide was reacted with Fe(II), Cd(II) and Cu(II) metal ions to afford six different coordination polymers. These complexes show diverse coordination modes and structural architectures.Figure optionsDownload as PowerPoint slideResearch highlights
► Six novel compounds bearing dps ligand were reported.
► Those compounds exhibit diverse structural architectures due to center ion and counteranion.
► Compound 1 shows visible yellow luminescence.