Photophysical processes of an intramolecular charge transfer fluorescent dye with carbazole units

Abstract

A carbazole-based compound with intramolecular charge transfer (ICT) characteristics, 3,6-bis-((N-ethylcarbazole-3-)-propene-1-keto)-N-ethylcarbazole (BCzPCz) was synthesized by N-alkylation, acetylation and aldol condensation. BCzPCz was further confirmed by IR and (1)H NMR. The central N-ethylcarbazole was connected with two N-ethylcarbazole units through the propenone group in BCzPCz. N-ethylcarbazole and carbonyl groups were electron donors (D) and acceptors (A), respectively. The UV-vis absorption and fluorescence characteristics of BCzPCz were also investigated in different solvents. Solvatochromism was attributed to ICT complex formation in singlet excited state. Magnitude of the change in the dipole moment was 24.78 D according to Lippert-Mataga equation. Fluorescence of BCzPCz was significantly affected by pH and was quenched in acidic medium. Fluorescence quantum yield of BCzPCz was 0.516 in ethanol. Experimental results showed its potential use as a fluorescence probe and as two-photon absorption material.

Effect of the Chloro-Substitution on Electrochemical and Optical Properties of New Carbazole Dyes

“…However, short-range specific interactions, e.g., self-aggregation and H -bond may be present. Similar solvatochromic effects have been demonstrated in studies on the 3,6-bis-(( N -ethylcarbazole-3-)-propene-1-keto)-N-ethylcarbazole [ 114 ]. In turn, Bingul at al.…”

pH‐responsive fluorescence chemical sensor constituted by conjugated polymers containing pyridine rings

“…In particular, conjugated oligomers and polymers with stimulusresponsive properties are good candidates for use as sensing materials because of their optical and electronic properties. The properties of chemical sensors using conjugated oligomers and polymers as sensing materials have been reported previously (19)(20)(21). Conjugated oligomers and polymers with ionic groups and hetero-rings showed changes in their optical properties due to chemical sensing of target chemical substances (22,23).…”

Carbazole–azine based fluorescence ‘off–on’ sensor for selective detection of Cu2+ and its live cell imaging

“…Carbazole and its derivatives possess highly conjugated systems, engage in active ICT and are used as electron‐donating chromophores . Carbazole compounds are promising candidates for electroluminescent and photorefractive devices because of their electron‐donating and hole‐transporting properties, and their remarkable application as fluorescent sensors .…”

“…[43][44][45][46][47][48][49][50][51][52][53][54][55][56][57][58] Carbazole and its derivatives possess highly conjugated systems, engage in active ICT and are used as electron-donating chromophores. [59][60][61][62][63] Carbazole compounds are promising candidates for electroluminescent and photorefractive devices because of their electron-donating and hole-transporting properties, and their remarkable application as fluorescent sensors. [64][65][66][67][68][69][70][71][72][73][74][75][76] In the bis-azine type ligand, the electron density is located on the [C=N−N=C] moiety.…”