Journal of the American Chemical Society
Article
there is no such driving force. With only one leaving group, the
indophenin products cannot fully aromatize.
Future Outlook. This method represents a new versatile
route to the construction of extended conjugated structures. In
addition to being a robust method, the starting materials are
readily available simple aromatics.
In principle, these diols could also undergo homocoupling
and potentially form conjugated polymers. However, we did
not observe homocoupling with these diols, even under more
forcing conditions such as refluxing in toluene. We are
currently exploring other scaffolds as well as conditions other
than Brønsted acids to promote polymerization.
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CONCLUSIONS
Ethylenedioxythiophene (EDOT)-Based Functional π-Conjugated
Molecules through Direct C-H Bond Arylations. Org. Lett. 2011, 13
■
We have disclosed a dehydrative C−C coupling methodology
using para-toluenesulfonic acid (p-TsOH) in toluene for the
preparation of highly conjugated molecules. Starting from
simple quinones, unsymmetrically substituted conjugated
molecules that are cumbersome to access through typical
cross-coupling methodologies are obtained in up to 97%
isolated yield. Products are obtained in two-steps, and the C−
C forming reactions are run under ambient conditions, at room
temperature or slightly elevated temperatures, rendering this
method extremely user-friendly.
(
15), 4068−4071.
11) Satoh, T.; Miura, M. Catalytic Direct Arylation of
Heteroaromatic Compounds. Chem. Lett. 2007, 36 (2), 200−205.
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Hetero)Arylation Polymerization in Biphasic Conditions. J. Am.
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(13) Pouliot, J. R.; Grenier, F.; Blaskovits, J. T.; Beaupre,
(
(
(
́
S.; Leclerc,
M. Direct (Hetero)Arylation Polymerization: Simplicity for Con-
jugated Polymer Synthesis. Chem. Rev. 2016, 116 (22), 14225−14274.
(14) Krebs, F. C.; Nyberg, R. B.; Jørgensen, M. Influence of Residual
Catalyst on the Properties of Conjugated Polyphenylenevinylene
Materials: Palladium Nanoparticles and Poor Electrical Performance.
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ASSOCIATED CONTENT
Supporting Information
■
*
S
(15) Leong, W. L.; Welch, G. C.; Kaake, L. G.; Takacs, C. J.; Sun, Y.;
Bazan, G. C.; Heeger, A. J. Role of Trace Impurities in the
Photovoltaic Performance of Solution Processed Small-Molecule Bulk
Heterojunction Solar Cells. Chem. Sci. 2012, 3 (6), 2103−2109.
Experimental procedures and methods, 1H and 13
NMR spectra, and UV−vis spectra (PDF)
C
(16) Olah, G. A.; Klumpp, D. A.; Neyer, G.; Wang, Q. The
Preparation of Substituted Phenanthrenes from Aryl Pinacols in
Superacid. Synthesis 1996, 1996, 321−323.
AUTHOR INFORMATION
(17) Klumpp, D. A.; Baek, D. N.; Prakash, G. K. S.; Olah, G. A.
Preparation of Condensed Aromatics by Superacidic Dehydrative
Cyclization of Aryl Pinacols and Epoxides 1a Depending on the
Strength of the Acid Catalyst, Ben-. J. Org. Chem. 1997, 62, 6666−
ORCID
6
(
671.
Notes
18) Vanveller, B.; Schipper, D. J.; Swager, T. M. Polycyclic
Aromatic Triptycenes: Oxygen Substitution Cyclization Strategies. J.
Am. Chem. Soc. 2012, 134 (17), 7282−7285.
(19) Xu, J.; Luo, Y.; Xu, H.; Chen, Z.; Miao, M.; Ren, H. Catalyst-
The authors declare no competing financial interest.
Controlled Chemodivergent Modification of Indoles with 2-
Furylcarbinols: Piancatelli Reaction vs Cross-Dehydrative Coupling
Reaction. J. Org. Chem. 2017, 82 (7), 3561−3570.
ACKNOWLEDGMENTS
■
This work was funded by the Air Force Office of Scientific
Research Grant No. 17RT0904. We thank Dr. Nathan A.
Romero for insightful discussions.
(20) Miao, M.; Luo, Y.; Li, H.; Xu, X.; Chen, Z.; Xu, J.; Ren, H.
Lewis Acid Catalyzed Regiospecific Cross-Dehydrative Coupling
Reaction of 2-Furylcarbinols with β-Keto Amides or 4-Hydroxycou-
marins: A Route to Furyl Enols. J. Org. Chem. 2016, 81 (12), 5228−
5235.
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