Deep red aggregation-induced CPL emission behavior of four-component tunable AIE-active chiral polymers via two FRET pairs mechanism. (9th November 2017) - Wang, Ziyu
Abstract: Two four-component chiral polymers with two Förster resonance energy transfer (FRET) pairs incorporating chiral 1, 1′-binaphthyl, 4, 7- di(thiophen-2-yl)-2, 1, 3-benzothiadiazole (DTBT), tetraphenylethene (TPE) and fluorene moieties were designed and synthesized via one-pot two-step of Pd-catalyzed Sonogashira reaction and Suzuki reaction by changing different ratios of DTBT chromophore and AIE-active TPE group. Both chiral polymers exhibit large Stokes shift (257 nm) and tunable red aggregation-induced emission (AIE) response behavior via two intramolecular FRET pairs by changing excitation wavelength. Interestingly, the chiral polymer with lower ratio of DTBT (P-1 ) shows obvious aggregation-induced circularly polarized luminescence (AICPL) emission signals in deep red region (around 650 nm) and higher g lum, which can reach as high as ±2.0 × 10 -3 in THF-H2 O mixtures. Graphical abstract: Highlights: Two four-component chiral AIE-active conjugated polymers were developed via two intramolecular FRET pairs. These polymers exhibit tunable red AIE behavior by changing excitation wavelength with 257 nm Stokes shift. These polymers show tunable deep red AICPL signals via different ratios of DTBT and TPE moieties with the highest g lum = ±2.0 × 10 −3 .