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Fluorescent properties of an azacrown-containing styryl derivative of naphthopyran: ion-binding response and photochemical switching off
The fluorescent properties of a recently synthesized photochromic naphthopyran containing a 1-aza-15-crown-5 moiety ( 1b ) and its crownless analogue ( 1a ) were studied. 1b emits fluorescence with a maximum at 528 nm, quantum yield 0.1 and characteristic lifetime 2.4 ns (in acetonitrile at room tem...
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Published in: | Photochemical & photobiological sciences 2013-10, Vol.12 (10), p.1803-1810 |
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Main Authors: | , , , , |
Format: | Article |
Language: | English |
Subjects: | |
Citations: | Items that this one cites Items that cite this one |
Online Access: | Get full text |
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Summary: | The fluorescent properties of a recently synthesized photochromic naphthopyran containing a 1-aza-15-crown-5 moiety (
1b
) and its crownless analogue (
1a
) were studied.
1b
emits fluorescence with a maximum at 528 nm, quantum yield 0.1 and characteristic lifetime 2.4 ns (in acetonitrile at room temperature). Its luminescence could be switched off photochemically in two ways using two parallel photochemical reactions characteristic for this type of naphthopyran. The first way is the irreversible
trans
-
cis
photoisomerization of a closed form (“stilbene-like reaction”). The second way is the thermally reversible reaction of closed form transition to the open form (“chromene-like reaction”). The fluorescence of
1b
is quenched by alkali earth metal cations by the mechanism of static quenching. Stability constants for 1?:?1 complexes of
1b
with Mg
2+
and Ba
2+
determined from Stern-Volmer plots are in agreement with that obtained by UV spectroscopy. |
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ISSN: | 1474-905X 1474-9092 |
DOI: | 10.1039/c3pp50051a |