A novel dimeric copper salicylate with an undissociated COOH group: Synthesis and crystal structure of [Cu2(HSal)(Sal)(2,2′-bpy)2](ClO4)

A dinuclear copper salicylate [Cu2(HSal)(Sal)(2,2′-bpy)2](ClO4) (1) (H2Sal = salicylic acid) has been synthesized and characterized with the aid of elemental analysis and infrared, ultraviolet and fluorescence spectroscopic studies. The molecular structure of 1, determined by single-crystal X-ray diffraction studies, shows the presence of incompletely deprotonated salicylate ligands in the complex. Hydrogen bonding interactions and π–π aromatic stacking lead to the formation of 2D polymeric structure in the solid state.