A dual-functional Zn-based coordination polymer as a catalyst for CO2 cycloaddition under mild conditions and a fluorescent probe for highly selective sensing of levofloxacin in aqueous solution

Abstract

A Zn(II) coordination polymer, [Zn(L)(mip)]_n (1) (L  = 1,3-bis(2-methylbenzimidazol-1-yl)− 2-propanol, H₂mip = 5-methylisophthalic acid) was synthesized by hydrothermal method and characterized. 1 featured a 1D chain and further extended 2D layer via C–H···O weak hydrogen bond interactions. As Lewis acid heterogeneous catalysts, 1 exhibits high activity and selectivity for the cycloaddition reaction of CO₂ with propylene epoxide (PO) under solvent free and mild conditions. Additionally, 1 can serve as a promising fluorescent probe for the detection of levofloxacin (LEV) in aqueous media. The quenching efficiency reaches 95.0% and a detection limit as low as 1.16 × 10⁻⁷ mol/L are achieved.