Dynamic Covalent Self‐sorting in Molecular and Polymeric Architectures Enabled by Spiroborate Bond Exchange

Abstract

AbstractSelf‐sorting is commonly observed in complex reaction systems, which has been utilized to guide the formation of single major by‐design molecules. However, most studies have been focused on non‐covalent systems, and using self‐sorting to achieve covalently bonded architectures is still relatively less explored. Herein, we first demonstrated the dynamic nature of spiroborate linkage and systematically studied the self‐sorting behavior observed in the transformation between spiroborate‐linked well‐defined polymeric and molecular architectures, which is enabled by spiroborate bond exchange. The scrambling between a macrocycle and a 1D helical covalent polymer led to the formation of a molecular cage, whose structures are all unambiguously elucidated by single‐crystal X‐ray diffraction. The results indicate that the molecular cage is the thermodynamically favored product in this multi‐component reaction system. This work represents the first example of a 1D polymeric architecture transforming into a shape‐persistent molecular cage, driven by dynamic covalent self‐sorting. This study will further guide the design of spiroborate‐based materials and open the possibilities for the development of novel complex yet responsive dynamic covalent molecular or polymeric systems.