Enantioselective Recognition of L-Lysine by ICT Effect with a Novel Binaphthyl-Based Complex

A novel triazole fluorescent sensor was efficiently synthesized using binaphthol as the starting substrate with 85% total end product yield. This chiral fluorescence sensor was proved to have high specific enantioselectivity for lysine. The fluorescence intensity ofR-1was found to increase linearly when the equivalent amount of L-lysine (0–100 eq.) was gradually increased in the system. The fluorescence intensity of L-lysine toR-1was significantly enhanced, accompanied by the red-shift of emission wavelength (389 nm to 411 nm), which was attributed to the enhanced electron transfer within the molecular structure, resulting in anICTeffect, while the fluorescence response of D-lysine showed a decreasing trend. The enantioselective fluorescence enhancement ratio for the maximum fluorescence intensity was 31.27 [ef = |(IL−I0)/(ID−I0)|, 20 eq. Lys], thus it can be seen that this fluorescent probe can be used to identify and distinguish between different configurations of lysine.Keywords:enantioselective recognition;ICT effect;intermolecular hydrogen bond