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Title: Gated, Selective Anion Exchange in Functionalized Self‐Assembled Cage Complexes
Abstract

Appending functional groups to the exterior of Zn4L4self‐assembled cages allows gated control of anion binding. While the unfunctionalized cages contain aryl groups in the ligand that can freely rotate, attaching inert functional groups creates a “doorstop”, preventing rotation and slowing the guest exchange rate, even though the interiors of the host cavities are identically structured. The effects on anion exchange are subtle and depend on multiple factors, including anion size, the nature of the leaving anion, and the electron‐withdrawing ability and steric bulk of the pendant groups. Multiple exchange mechanisms occur, and the nature of the external groups controls associative and dissociative exchange processes: these bulky groups affect both anion egress and ingress, introducing an extra layer of selectivity to the exchange. Small changes can have large effects: affinities for anions as similar as PF6and SbF6can vary by as much as 400‐fold between identically sized cavities.

 
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Award ID(s):
2002619
NSF-PAR ID:
10398160
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Chemistry – A European Journal
Volume:
29
Issue:
11
ISSN:
0947-6539
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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