Tuning sensing efficacy of anthraimidazoledione-based charge transfer dyes : nitro group positioning impact

Anthraimidazoledione-based optical sensors have been designed by varying the position of the nitro functional group. All three positional isomers showed highly colored, photostable optical signals owing to intramolecular charge transfer interactions. Despite having the same anion-binding site (imidazole unit), the selectivity and sensitivity of the compounds depend on the positioning of the nitro group. The selectivity was fairly good for the meta isomer, followed by the ortho and para isomers, respectively. In contrast, the sensitivity towards anions followed a completely opposite trend, with the para isomer being the most sensitive one towards anions. Interestingly, the color changing response along the turn-on fluorescence signal was observed only with CN- ions in a semi-aqueous environment. Though the introduction of water as a co-solvent could improve the selectivity, the sensitivity was found to be slightly less than that observed in pure organic medium. Mechanistic studies indicated hydrogen bonding interactions between the imidazole -NH proton and cyanide, which further facilitated the extent of intramolecular charge transfer.

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - volume:53

Enthalten in:

Dalton transactions (Cambridge, England : 2003) - 53(2024), 14 vom: 02. Apr., Seite 6343-6351

Sprache:

Englisch

Beteiligte Personen:

Chettri, Bimal [VerfasserIn]
Pal, Animesh [VerfasserIn]
Jha, Satadru [VerfasserIn]
Dey, Nilanjan [VerfasserIn]

Links:

Volltext

Themen:

Journal Article

Anmerkungen:

Date Revised 02.04.2024

published: Electronic

Citation Status PubMed-not-MEDLINE

doi:

10.1039/d3dt04172g

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM369777956