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Title: Strong Ground‐ and Excited‐State Charge Transfer in C3 ‐Symmetric Truxene‐Derived Phenothiazine‐Tetracyanobutadine and Expanded Conjugates
Abstract

TheC3‐symmetric star‐shaped phenothiazene‐substituted truxene1was reacted with the electron acceptors tetracyanoethylene (TCNE) and 7,7,8,8‐tetracyanoquinodimethane (TCNQ). The cycloaddition–retroelectrocyclization reaction yields the conjugates2and3. A combination of spectral, electrochemical, and photophysical investigations of2and3reveals that the functionalization of the triple bond has a pronounced effect on their ground and excited‐state interactions. Specifically, the existence of strong ground‐state interactions between phenothiazine and the electron‐accepting groups results in charge‐transfer states, while subsequent ultrafast charge separation yields electron transfer products. This is unprecedented not only in phenothiazine chemistry but also in tetracyanobutadiene‐ and dicyanoquinodimethane‐derived donor–acceptor conjugates. Additionally, by manipulating spectroelectrochemical data, a spectrum of the charge‐separated species is construed for the first time, and shown to be highly useful in interpreting the rather complex transient spectra.

 
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NSF-PAR ID:
10086462
Author(s) / Creator(s):
 ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie International Edition
Volume:
58
Issue:
13
ISSN:
1433-7851
Page Range / eLocation ID:
p. 4350-4355
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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