Three luminescent d10 metal coordination polymers assembled from a semirigid V-shaped ligand with high selective detecting of Cu2+ ion and nitrobenzene

•Three coordination polymers with chiral helical-layer have been obtained.•1 Can luminescent detect Cu2+ ion in aqueous media and nitrobenzene.•Racemic mixture or mesomer compounds can be obtained by controlling the reaction conditions.

Three 2D luminescent coordination polymers with helical frameworks, [ZnL2]n (1) and {[ML2]·(H2O)}n (M=Zn (2), Cd (3)) (HL=4-((2-methyl-1 H-imidazol-1-yl)methyl)benzoic acid), have been assembled under hydro(solvo)thermal conditions. Complex 1 is in chiral space group and displays a rare 2D→2D 2-fold parallel interpenetrated layer network with two types of chiral double helixes. Interestingly, the single crystal structure analyses indicate the coexistence of enantiomers la and 1b in one pot, while the bulk crystallization of 1 are racemic mixtures based on the CD measurement. 2 and 3 are isostructural, in the structure, there are two kinds of 2D chiral helical-layers which stack in an -ABAB- sequence leading to the overall structure are mesomer and achiral. All compounds display intense luminescence in solid state at room temperature with high chemical and thermal stability. More importantly, 1 has been successfully applied in the detection of Cu2+ ions in aqueous media and nitrobenzene and the probable detecting mechanism was also discussed.

Graphical abstractThree luminescent d10 metal coordination polymers with helical-layer based on 4-((2-methyl-1H-imidazol-1-yl)methyl)benzoic acid have been obtained. Compound 1 shows high selective detecting for Cu2+ ion in aqueous and nitrobenzene.Figure optionsDownload full-size imageDownload as PowerPoint slide