Zinc-mediated rigid cyclization enables highly enantioselective fluorescent recognition of chiral amino alcohols in aqueous phase.

Abstract

Chiral amino alcohols represent a crucial class of chiral amines with significant applications across various fields. Herein, a novel BINOL-based fluorescent probe(R)-5, featuring dual aldehyde and hydroxyl functionalities, was rationally designed and synthesized. (R)-5 exhibited excellent enantioselective recognition of D-valinol over L-valinol in aqueous media, with a detection limit (LOD) of 12.75 μM for D-valinol and an enantioselective fluorescence enhancement ratio [ef = (ID - I0)/(IL-I0)] of 20.50. Comprehensive structural characterization suggests that the observed fluorescence enhancement is attributed to the formation of a rigid cyclic coordination complex, facilitated by coordination between the imine and Zn2+. This work presents a novel and efficient strategy for the simultaneous determination of the enantiomeric composition and concentration of chiral amino alcohols.