based on the BODIPY3 have been applied as a Ag+ sensor,3l
Na+ sensor,3k NO sensor,3h Hg2+ sensor,3a,3g Zn2+ sensor,3c,3e
Ca2+ sensor,3f F- sensor,3i and pH sensor.3j
New BODIPY Derivatives as OFF-ON
Fluorescent Chemosensor and Fluorescent
Chemodosimeter for Cu2+: Cooperative
Selectivity Enhancement toward Cu2+
Pb2+ is one of the important targets because of the adverse
health effects of lead exposure, particularly in children.4 The
design of a Cu2+ sensor has also received intensive attraction
since this metal ion is a significant environmental pollutant and
an essential trace element in biological system.5 However, Cu2+
and Pb2+ are known as inherent quenching metal ions,1d,6 and
therefore, relatively few reports are available for “off-on”-type
fluorescent chemosensors, which can selectively recognize Cu2+7
and Pb2+ ions.8
Xin Qi,† Eun Jin Jun,† Li Xu,† Sung-Jin Kim,†
Jay Sung Joong Hong,‡ Yeo Joon Yoon,† and
Juyoung Yoon*,†
Department of Chemistry and DiVision of Nano Science,
Ewha Womans UniVersity, 11-1 Daehyon-Dong, Sodaemun-Ku,
Seoul 120-750, South Korea, and Interdisciplinary Program of
Biochemical Engineering and Biotechnology, Seoul National
UniVersity, San 56-1, Shilim-dong, Gwanak-gu,
We report herein utilizing new BODIPY derivatives (1 and
2) as an “off-on” fluorescent chemosensor and fluorescent
chemodosimeter for Cu2+ and Pb2+. Compound 1 displayed
selective and large chelation enhanced fluorescence (CHEF)
effects with Pb2+ and Cu2+ among the metal ions examined.
On the other hand, compound 2, a fluorescent chemodosimeter,
effectively recognized Cu2+ via a selective hydrolysis of acetyl
group.
Seoul 151-742, South Korea
ReceiVed December 12, 2005
The direct synthesis of the target 1 based on the reported
route3j using 4-N,N-bis-(2-hydroxyethyl)aminobenzaldehyde and
2,4-dimethylpyrrole failed due to the poor solubility of the
aldehyde in methylene chloride. Therefore, the hydroxyl groups
on the aldehyde were then first acetylated to improve the
solubility. Although the monoacetylated product was also
soluble enough in condensation condition, the bisacetylated
derivative was preferential, considering the ease of the separation
of 2 (Scheme 1). In the X-ray structure of 2 shown in Figure 1
(see S-Figure 1 in the Supporting Information for 1), a C2 axis
passes through the B1, C7, C8, and C11 atoms in 2. The phenyl
and pyrrole rings are planar, with an average deviation of 0.0033
and 0.0102 Å, respectively. Similarly, the phenyl and pyrrole
New 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY)
derivatives (1 and 2) were synthesized as an “off-on”
fluorescent chemosensor and fluorescent chemodosimeter for
Cu2+ and Pb2+. Compound 1 displayed selective and large
chelation enhanced fluorescence effects with Pb2+ and Cu2+
among the metal ions examined. On the other hand,
compound 2, a fluorescent chemodosimeter, effectively
recognized Cu2+ via a selective hydrolysis of the acetyl
group.
(3) (a) Rurack, K.; Kollmannsberger, M.; Resch-Genger, U.; Daub, J. J.
Am. Chem. Soc. 2000, 122, 968. (b) Rurack, K.; Kollmannsberger, M.; Daub,
J. Angew. Chem., Int. Ed. 2001, 40, 385. (c) Turfan, B.; Akkaya, E. U.
Org. Lett. 2002, 4, 2857. (d) Gee, K. R.; Rukavishnikov, A.; Rothe, A.
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2003, 44, 8265. (g) Moon, S. Y.; Cha, N. R.; Kim, Y. H.; Chang, S.-K. J.
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H.; Nagano, T. J. Am. Chem. Soc. 2004, 126, 3357. (i) Coskun, A.; Akkaya,
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Sensors based on the ion-induced changes in fluorescence
appear to be particularly attractive due to the simplicity and
high detection limit of the fluorescence.1 Over the past few
years, 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY)
derivatives have been utilized as useful fluorophores because
of their advantages, such as high excitation coefficients, high
fluorescence quantum yields, and high stability against light and
chemical reactions.2 Recently, the fluorescent chemosensors
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Pham, S. M.; Leblanc, R. M. J. Am. Chem. Soc. 2003, 125, 2680.
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† Ewha Womans University.
‡ Seoul National University.
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10.1021/jo052542a CCC: $33.50 © 2006 American Chemical Society
Published on Web 03/10/2006
J. Org. Chem. 2006, 71, 2881-2884
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