Sequential Recognition of Bisulfate and Acetate by a Ruthenium(II) Complex: Experimental and Theoretical Studies

• Published in: ChemPhotoChem Vol. 8; no. 1
• Main Authors: Bazany‐Rodríguez, Iván. J., García‐Rojas, Liliana Margarita, Guadalupe Hernández, José, Thangarasu, Pandiyan
• Format: Journal Article
• Language: English
• Published: 01-01-2024
• ISSN: 2367-0932; 2367-0932
• DOI: 10.1002/cptc.202300145

Abstract
New complex
[RuLCl
2
(PPh
3
)]
(L=N,N‐bis(2‐hydroxy‐5‐nitrobenzaldehyde)‐2,2’‐diaminodiethylamine) was prepared and characterized analytically and was employed as a luminescent chemosensor for the detection of anions. The results show that
[RuLCl
2
(PPh
3
)]
can detect HSO
4
−
and AcO
−
selectively and in sequential order in H
2
O‐CH
3
CN (8 : 2, v/v) at pH 7.0. The spectral binding, titration, and interference analyses reveal that the addition of HSO
4
−
to [
RuLCl
2
(PPh
3
)]
results in an intense fluorescence emission (I
F
/I
0
=6.55). This shows that HSO
4
−
interacts suitably with the complex to switch ON the fluorescence which could be explained by inhibition of a PET mechanism as the above addition forms
[RuLCl(HSO
4
)(PPh
3
)]
in the excited state. Selectivity interaction of complex
[RuLCl
2
(PPh
3
)]
with HSO
4
−
results in the formation of
[RuLCl(HSO
4
)(PPh
3
)]
in water but the system exhibits negligible change in its emission except for AcO
−
, which enhances fluorescence intensity. For the addition of AcO
−
to
[RuLCl
2
(PPh
3
)]
, the system
[RuLCl(AcO)(PPh
3
)]
is formed, however, the adding of HSO
4
−
to [
RuLCl(AcO)(PPh
3
)]
does not show any change in the intensity, suggesting that there exists a logic gate function for the addition of HSO
4
−
followed by AcO
−
to
[RuLCl
2
(PPh
3
)]
. This finding is interesting because
[RuLCl
2
(PPh
3
)]
can act as a fast selective chemosensor for the sequential detection of HSO
4
−
and AcO
−
.