A new two-dimensional homochiral cadmium(II) coordination polymer: synthesis, structure determination, optical properties, and fluorescent sensing

A new two-dimensional (2D) homochiral cadmium(II) coordination polymer, {[Cd4(OH)2(L)2(pea)4]·CH3OH}n (1) (pea = (S)-1-phenylethanamine), was solvothermally synthesized based on an enantiomerically pure chiral ligand (S)-5-(((1-carboxy-2-phenylethyl)amino) methyl)isophthalic acid (H3L). Crystal structure analysis shows that 1 is a 2D homochiral framework consisting of coaxial double-helical chains where a pair of left- and right-handed 21 helixes shares tetranuclear Cd cluster subunits [Cd4(μ3-OH)2]. Topologically, 1 is an interesting 3,6-connected network with the point symbol of (43)2(46·66·83). The thermal stability and solid-state optical properties, including circular dichroism, and nonlinear optical and luminescent properties of 1 were systematically investigated. Furthermore, the fluorescence response of 1 to various common solvents and metal ions was preliminarily studied. Interesting enough, N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMA), acetone and Fe3+ ion have strong quenching effect on the fluorescence of 1, indicating that 1 has certain potential application in the visual detection of these species.