Light-Driven Chiral Switching of Supramolecular Metallacycles with Photoreversibility

Abstract

The construction of artificial chiral self-assembled systems has evolved to be one of the most attractive topics within supramolecular chemistry and materials science. However, stimuli-responsive chirality transcription with enantiospecific photoreversibility still remains challenging for chiral metallasupramolecular structures because of the lack of appropriate building blocks. Herein, we present a chiral photoresponsive family of diarylethene-containing dipyridyl donors and their coordination-driven self-assembly behavior with the 120° di-platinum(II) acceptor. The photochromic trimer units in the assembled metallacycles exhibit an unprecedented concerted photoconversion process without a step-by-step transformation. By taking advantage of the full-separated photoactive dipyridyl donor enantiomers based on the sterically hindered system, we have successfully achieved the phototriggered chirality transformation in supramolecular multi-dithienylethene metallacycles arising from axial helicity and central asymmetry, thereby establishing light-driven control in circular dichroism. Such unique photoreversible self-assembled metallacycles with photoinduced enantiospecificity enable the potential chemical platform for bistable chiroptical switching and non-destructive information encoding.Artificial chiral supramolecular architectures have been continuously aimed at mimicking natural biological macromolecules. However, light-driven chirality transcription with photoreversible enantiospecificity remains challenging. In this manuscript, we focus on a new family of light-driven chiral supramolecular metallacycles with a concerted, reversible, and enantiospecific transformation based on a unique chiral photoresponsive building block. As a delicate example of light-driven chiral supramolecular metallacycles with a reversible and enantiospecific transformation, we believe that the fundamental work presented herein is very guidable for developing light-driven supramolecular architectures, especially for stimuli-responsive chiral functional materials. The longer-term ambition is to establish a new platform for constructing chiral non-invasion photoswitching and extending their potential application in molecular information processing.An unprecedented light-driven chiral switching supramolecular system exhibits reversible and enantiospecific transformation along with a unique concerted photoconversion process. It is guidable for the development of light-driven supramolecular architectures, especially for stimuli-responsive chiral functional materials.