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Title: Rapid Access to Encapsulated Molecular Rotors via Coordination‐Driven Macrocycle Formation
Abstract

Macrocycle formation that relies upontransmetal coordination of appropriately placed pyridine ligands within an arylene ethynylene construct provides rapid and reliable access to molecular rotators encapsulated within macrocyclic stators. Showing no significant close contacts to the central rotators, X‐ray crystallography of AgI‐coordinated macrocycles provides plausibility for unobstructed rotation or wobbling of rotators within the central cavity. Solid‐state13C NMR of PdII‐coordinated macrocycles supports the notion of unobstructed movement of simple arenes in the crystal lattice. Solution1H NMR studies indicate complete and immediate macrocycle formation upon the introduction of PdIIto the pyridyl‐based ligand at room temperature. Moreover, the formed macrocycle is stable in solution; a lack of significant changes in the1H NMR spectrum upon cooling to −50 °C is consistent with the absence of dynamic behavior. The synthetic route to these macrocycles is expedient and modular, providing access to rather complex constructs in four simple steps involving Sonogashira coupling and deprotection reactions.

 
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Award ID(s):
1903581 1903593
NSF-PAR ID:
10434537
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Chemistry – A European Journal
Volume:
29
Issue:
50
ISSN:
0947-6539
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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