TY  - JOUR
A1  - Ast, Sandra
A1  - Fischer, Tobias
A1  - Müller, Holger
A1  - Mickler, Wulfhard
A1  - Schwichtenberg, Mathias
A1  - Rurack, Knut
A1  - Holdt, Hans-Jürgen
T1  - Integration of the 1,2,3-Triazole "Click" Motif as a potent signalling element in metal ion responsive fluorescent probes
JF  - Chemistry - a European journal
N2  - In a systematic approach we synthesized a new series of fluorescent probes incorporating donoracceptor (D-A) substituted 1,2,3-triazoles as conjugative -linkers between the alkali metal ion receptor N-phenylaza-[18]crown-6 and different fluorophoric groups with different electron-acceptor properties (4-naphthalimide, meso-phenyl-BODIPY and 9-anthracene) and investigated their performance in organic and aqueous environments (physiological conditions). In the charge-transfer (CT) type probes 1, 2 and 7, the fluorescence is almost completely quenched by intramolecular CT (ICT) processes involving charge-separated states. In the presence of Na+ and K+ ICT is interrupted, which resulted in a lighting-up of the fluorescence in acetonitrile. Among the investigated fluoroionophores, compound 7, which contains a 9-anthracenyl moiety as the electron-accepting fluorophore, is the only probe which retains light-up features in water and works as a highly K+/Na+-selective probe under simulated physiological conditions. Virtually decoupled BODIPY-based 6 and photoinduced electron transfer (PET) type probes 35, where the 10-substituted anthracen-9-yl fluorophores are connected to the 1,2,3-triazole through a methylene spacer, show strong ion-induced fluorescence enhancement in acetonitrile, but not under physiological conditions. Electrochemical studies and theoretical calculations were used to assess and support the underlying mechanisms for the new ICT and PET 1,2,3-triazole fluoroionophores.
KW  - charge transfer
KW  - click chemistry
KW  - electron transfer
KW  - fluorescent probes
KW  - metal ions
Y1  - 2013
U6  - https://doi.org/10.1002/chem.201201575
SN  - 0947-6539
VL  - 19
IS  - 9
SP  - 2990
EP  - 3005
PB  - Wiley-VCH
CY  - Weinheim
ER  -