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Title: Structural deformation and host–guest properties of doubly-reduced cycloparaphenylenes, [ n ]CPPs 2− ( n = 6, 8, 10, and 12)
Chemical reduction of several cycloparaphenylenes (CPPs) ranging in size from [8]CPP to [12]CPP has been investigated with potassium metal in THF. The X-ray diffraction characterization of the resulting doubly-reduced [ n ]CPPs provided a unique series of carbon nanohoops with increasing dimensions and core flexibility for the first comprehensive structural analysis. The consequences of electron acquisition by a [ n ]CPP core have been analyzed in comparison with the neutral parents. The addition of two electrons to the cyclic carbon framework of [ n ]CPPs leads to the characteristic elliptic core distortion and facilitates the internal encapsulation of sizable cationic guests. Molecular and solid-state structure changes, alkali metal binding and unique size-dependent host abilities of the [ n ]CPP 2− series with n = 6–12 are discussed. This in-depth analysis opens new perspectives in supramolecular chemistry of [ n ]CPPs and promotes their applications in size-selective guest encapsulation and chemical separation.  more » « less
Award ID(s):
2003411 1608628 1726724 1834750 1800586
PAR ID:
10199464
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Chemical Science
Volume:
11
Issue:
35
ISSN:
2041-6520
Page Range / eLocation ID:
9395 to 9401
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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