Self-Assembled Polydiacetylene Vesicle and Helix with Chiral Interface for Visualized Enantioselective Recognition of Sulfinamide

Abstract

An l-glutamic acid terminated amphiphilic diacetylene was designed and found to self-assemble into vesicles in water and supramolecular gel with helical structures in mixed methanol/water solvent. Both the vesicles and the helices underwent topochemical photopolymerization under UV irradiation and changed to a blue color. During the self-assembly and photopolymerization, the chirality of localized l-glutamic acid was successfully transferred to polydiacetylene (PDA), which resulted in obvious CD signals in the PDA blue phase. Interestingly, the CD signals for PDA vesicles and helices were opposite due to the different packing modes in the PDA skeleton. However, although these two assembly systems own opposite supramolecular chirality, both of them showed the same enantioselective recognition of sulfinamide enantiomers, in which the assemblies with S-enantiomer turned red while the other remained blue in the presence of the R-enantiomer. It is suggested that the chiral interface composed of l-glutamic acid played an important role in the enantioselective recognition. This work revealed the function of molecular and supramolecular chirality in the supramolecular self-assembly system.