A tetraphenylethene-based chiral polymer: an AIE luminogen with high and tunable CPL dissymmetry factor

A tetraphenylethene (TPE)-based chiral polymer (TPETyr) was synthesized by the polymerization of 1,2-bis(4-ethynylphenyl)-1,2-diphenylethene (M-1) and 3',5'-diiodo-N- alpha -tert -butoxycarbonyl-O-octyl-l-tyrosine methyl ester (M-2) viaSonogashira cross-coupling. Interestingly, the generated luminogen emits weak fluorescence in THF solution, but becomes strongly luminescent as nanoparticle suspensions upon addition of water, demonstrating a novel phenomenon of aggregation-induced emission (AIE). The resulting TPETyr can also exhibit a large CPL dissymmetry factor (g sub(lum)) in both solution and aggregate states. More importantly, the g sub(lum) can be tuned in the range of 0.44 to 0.08 by changing the content of water in THF solution.