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Abstract Cyclophanes are a venerable class of macrocyclic and cage compounds that often contain unusual conformations, high strain, and unusual properties. However, synthesis of complex, functional derivatives remains difficult due to low functional group tolerance, high dilution, extreme reaction conditions, and sometimes low yields using traditional stepwise synthetic methods. “Design of experiments” (DOE) is a method employed for the optimization of reaction conditions, and we showcase this approach to generate a dramatic increase in the yield of specific targets from two different self‐assembling systems. These examples demonstrate that DOE provides an additional tool in tuning self‐assembling, dynamic covalent systems.
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Dynamic Covalent Self‐sorting in Molecular and Polymeric Architectures Enabled by Spiroborate Bond Exchange
Abstract Self‐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.
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- PAR ID:
- 10419154
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 62
- Issue:
- 27
- ISSN:
- 1433-7851
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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