Organic Letters
Letter
months under argon and for hours in the presence of oxygen.
These features are of great interest from the perspective of air-
operating electrochromic devices and molecular switches.
Isolation and investigations of 1 as a solid material are in
progress.
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Characterization of a Highly Reducing Neutral “Extended Viologen”
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ASSOCIATED CONTENT
Supporting Information
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as Liquid Electrochromic Devices. Chem. - Eur. J. 2014, 20, 3982.
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f) Chen, L.; Hartl, F.; Colquhoun, H. M.; Greenland, B. W.
1
2
Prediction of cathodic E1/2 and E1/2 values for viologen-containing
conjugated unimers and dimers from calculated pK values of the
b
Experimental procedures, spectro-electrochemical and
EPR spectra, hyperfine coupling constants, calculated
molecular orbitals, X-ray crystal data (PDF)
aromatic substituents. Tetrahedron Lett. 2017, 58, 1859.
(6) Chen, L.; Willcock, H.; Wedge, C. J.; Hartl, F.; Colquhoun, H.
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CCDC 1846774 contains the supplementary crystallographic
bridge Crystallographic Data Centre, 12 Union Road,
Cambridge CB2 1EZ, UK; fax: +44 1223 336033.
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Narrow-Bandgap Chalcogenoviologens for Electrochromism and
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AUTHOR INFORMATION
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ORCID
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018, 57, 4897.
10) (a) Stolar, M.; Borau-Garcia, J.; Toonen, M.; Baumgartner, T.
Synthesis and Tunability of Highly Electron-Accepting, N-Benzylated
Phosphaviologens”. J. Am. Chem. Soc. 2015, 137, 3366. (b) Stolar,
Author Contributions
“
M.; Baumgartner, T. Functional conjugated pyridines via main-group
element tuning. Chem. Commun. 2018, 54, 3311.
All authors have approved the final version of the manuscript.
Notes
(11) Greulich, T. W.; Yamaguchi, E.; Doerenkamp, C.; Lubbes-
̈
meyer, M.; Daniliuc, C. G.; Fukazawa, A.; Eckert, H.; Yamaguchi, S.;
Studer, A. Synthesis and Physical Properties of Strained Doubly
Phosphorus-Bridged Biaryls and Viologens. Chem. - Eur. J. 2017, 23,
The authors declare no competing financial interest.
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029.
ACKNOWLEDGMENTS
12) Yang, Y.; Liu, D.; Song, M.; Shi, D.; Liu, B.; Cheng, K.; Lu, Y.;
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Liu, H.; Yang, M.; Wang, W.; Li, J.; Wei, J. Facile Synthesis of π-
Extended Viologens: Electron-Deficient Polycyclic Aza-aromatics.
Chem. - Eur. J. 2017, 23, 7409.
The authors thank the “Agence National de la Recherche”
(
ANR-12-BS07-0014-01), the International Center for Fron-
tier Research in Chemistry (CSC-JWE-16; JWE-CSC-0003),
the CNRS, and the Univ. of Strasbourg for funding and C.
Bailly for the structure determination. T.B. thanks the Canada
Research Chairs program for financial support. S.C. and N.L.B.
thank REseau NAtional de Rpe interDisciplinaire, RENARD,
(13) (a) Fielden, R.; Summers, L. A. The 2,2′-dicyano-1,1′-
dimethyl-4,4′-bipyridylium di-cation: A viologen indicator with a
high redox potential. Experientia 1974, 30, 843. (b) Kuzuya, M.;
Kondo, S.; Murase, K. A novel single electron transfer in solid-state
organic compounds: mechanically induced reduction of dipyridinium
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S.; Juetten, M. J.; Wood, S. A.; Winter, A. H. The Viologen Cation
Radical Pimer: A Case of Dispersion-Driven Bonding. Angew. Chem.,
Int. Ed. 2017, 56, 9435.
Fed ation IR-RPE CNRS 3443.
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