Étienne Knipping et al. / Tetrahedron Letters 52 (2011) 4385–4387
4387
Figure 3. Absorbance (top panels) and fluorescence (bottom panels) pictures of 2 (A) and 4 (B) in dichloromethane with various divalent metals. The fluorescence pictures
were taken by irradiating the samples with a UV lamp. From left to right: Mg2+, Al2+, Fe2+, Co2+, Ni2+, Cu2+, Cd2+, Zn2+, Hg2+
.
The fluorescence turn-on was further investigated with various
divalent metals. As seen in Figure 3, the fluorescence of 2 could be
triggered by Mg2+, Al2+, Zn2+, Cd2+, Hg2+ and Pb2+. Conversely, the
fluorescence of 4 could selectively be turned-on with Zn2+and to
a certain degree with Cd2+ at room temperature. Coordination of
4 with various metals also caused bathochromic shifts in the absor-
bance relative to the native 4.
Supplementary data
Supplementary data associated with this article can be found, in
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hydroxyquinoline azomethine was found. The fluorescence was
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NSERC Canada is thanked for DG, SRG, and RTI grants, and CFI is
thanked for equipment funding. The Centre for Self-Assembled
Chemical Structures (CSACS) is also acknowledged. S.D. thanks
NSERC for a graduate scholarship. Both E.K. and I.U.R. acknowledge
graduate scholarships from both the Direction des Relations Inter-
nationales of the Université de Montréal and the Région Aquitaine.
N.M. thanks CSACS for an undergraduate scholarship.
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