Journal of the American Chemical Society
Article
decreasing pH (ON1−OFF−ON1 output). An ON1−OFF−
ON1 photoswitch driven by a mixed output (Cu2+, Ag+) has
been recently described.27 The ON1−OFF−ON2 output is
more rare: besides the two systems of the type receptor/F−,
previously reported,11 and described here, it was observed with
a chelating agent containing the methoxy-quinoline subunit and
was driven by a change of the concentration of Ag+.28
ACKNOWLEDGMENTS
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This research was supported by the Italian Ministry of
University and Research (project PRIN: InfoChem).
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CONCLUSION
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Agostini, A.; Martínez-Manez, R.; Sancenon, F. Chem. Soc. Rev. 2013,
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L1H and L2H are simple molecules and anion sensors of poorly
sophisticated design. Nevertheless, their optical response is
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ASSOCIATED CONTENT
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S
* Supporting Information
Synthesis and characterization of L1H and L2H; details on
crystallographic studies (ORTEP views, tables with bond
distances and angles of H-bonding interactions); spectra
1
taken over the course of UV−vis, emission and H NMR
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Correction Program; University of Gottingen: Gottingen, Germany,
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titration experiments; excitation and emission spectra in BuCN
at 77 K. This material is available free of charge via the Internet
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AUTHOR INFORMATION
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(16) Sheldrick, G. M. Acta Crystallogr. 2008, A64, 112−122.
(17) Steiner, T. Angew. Chem., Int. Ed. 2002, 41, 48−76.
Corresponding Author
(18) (a) Kerr, C. E.; Mitchell, C. D.; Headrick, J.; Eaton, B. E.;
Netzel, T. L. J. Phys. Chem. B 2000, 104, 1637−1650. (b) Pereira, R.
V.; Gehlen, M. H. Chem. Phys. Lett. 2006, 426, 311−317.
Notes
The authors declare no competing financial interest.
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