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Title: Dissipative Formation of Covalent Basket Cages
Abstract

Living systems use chemical fuels to transiently assemble functional structures. As a step toward constructing abiotic mimics of such structures, we herein describe dissipative formation of covalent basket cage CBC5by reversible imine condensation of cup‐shaped aldehyde2(i.e., basket) with trivalent aromatic amine4. This nanosized [4+4] cage (V=5 nm3,Mw=6150 Da) has shape of a truncated tetrahedron with four baskets at its vertices and four aromatic amines forming the faces. Importantly,tris‐aldehyde basket2and aliphatictris‐amine7undergo condensation to give small [1+1] cage6. The imine metathesis of6and aromatictris‐amine4into CBC5was optimized to bias the equilibrium favouring6. Addition of tribromoacetic acid (TBA) as a chemical fuel perturbs this equilibrium to result in the transient formation of CBC5, with subsequent consumption of TBA via decarboxylation driving the system back to the starting state.

 
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PAR ID:
10370991
Author(s) / Creator(s):
 ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie International Edition
Volume:
61
Issue:
33
ISSN:
1433-7851
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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