The amplified circularly polarized luminescence emission response of chiral 1,1′‐binaphthol‐based polymers via Zn(II)‐coordination fluorescence enhancement

Abstract

ABSTRACTTwo kinds of chiral 1,1′‐binaphthol (BINOL)‐based polymer enantiomers were designed and synthesized by the polymerization of 5,5′‐((2,2′‐bis (octyloxy)‐[1,1′‐binaphthalene]‐3,3′‐diyl)bis(ethyne‐2,1‐diyl))bis(2‐hydroxybenzaldehyde) (M1) with alkyl diamine (M2) via nucleophilic addition–elimination reaction. The resulting chiral polymers can exhibit mirror image cotton effects either in the absence or in the presence of Zn2+ ion. Almost no fluorescence or circularly polarized luminescence (CPL) emission could be observed for two chiral BINOL‐based polymer enantiomers in the absence of Zn2+. Interestingly, the chiral polymers can show strong fluorescence and CPL response signals upon the addition of Zn2+, which can be attributed to Zn2+‐coordination fluorescence enhancement effect. This work can develop a new strategy on the design of the novel CPL materials via metal‐coordination reaction. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 1282–1288