Two new compounds assembled by 2, 3, 3′,4′-biphenyl tetracarboxylic acid: Luminescent properties for detection of acetylacetone

Abstract

One novel coordination polymer (CP) and one new supramolecular compound based on an unsymmetrical tetracarboxylate, namely, [Cu2(bptc) (bpy)2]·2H2O (H4bptc ​= ​2,3,3′,4′-biphenyl tetracarboxylic acid; bpy ​= ​2,2′-bipyridine) 1, [Ni(phen)3](H3bptc)2 (phen ​= ​1,10-phenanthroline) 2 have been solvothermally synthesized. Single-crystal X-ray diffraction analysis indicates that CP 1 displays a 1-D chain structure, which self-assembles into a final 3-D supramolecular network via the interchain π⋯π interactions. Supramolecular compound 2 is a phen-propagated mononuclear Ni(II) complex with H3bptc− as the templating agent. Notablely, the H4bptc molecules are uncoordinated and only act as the guest molecules. Luminescence investigations indicate that compound 2 can sensitively and selectively detect acetylacetone (acac) with high KSV value of 9.67 ​× ​104 ​M−1 and low limit of detection (LOD) of 18.9 ​ppb. In addition, the probable quenching mechanisms are also investigated.