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Title: Stepwise Generation of Mono‐, Di‐, and Triply‐Reduced Warped Nanographenes: Charge‐Dependent Aromaticity, Surface Nonequivalence, Swing Distortion, and Metal Binding Sites
Abstract

The stepwise chemical reduction of a molecular warped nanographene (WNG) having a negatively curved π‐surface and defined C80H30composition with Cs metal used as the reducing and complexing agent allowed the isolation of three different reduced states with one, two, and three electrons added to itsπ‐conjugated system. This provided a unique series of nanosized carbanions with increasing negative charge for in‐depth structural analysis of consequences of controlled electron charging of non‐planar nanographenes, using X‐ray crystallographic and computational tools. The 3D molecular electrostatic potential (MEP) maps identified the negative charge localization at the central part of the WNG surface where selective coordination of Cs+ions is confirmed crystallographically. In‐depth theoretical investigation revealed a complex response of the WNG to the stepwise electron acquisition. The extended and contorted π‐surface of the WNG undergoes subtle swinging distortions that are accompanied by notable changes in the electronic structure and site‐dependent aromaticity of the resulting carbanions.

 
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Award ID(s):
2003411
NSF-PAR ID:
10307809
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie International Edition
Volume:
60
Issue:
48
ISSN:
1433-7851
Page Range / eLocation ID:
p. 25445-25453
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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