2,3‐Di(thiophen‐2‐yl)quinoxaline Amine Derivatives: Yellow‐Blue Fluorescent Materials for Applications in Organic Electronics

Abstract

In this work, we have designed and synthesized new donoracceptor (D-A) type, 2,3-di(thiophen-2-yl)quinoxaline based amine derivatives (2-10). These compounds contain diaryl/ heterocyclic amine segment and quinoxaline core as an electron donor and acceptor respectively. The synthesized molecules were fully characterized by standard spectroscopic techniques. Absorption spectra of all compounds showed intramolecular charge transfer (ICT) transition in the range of 390 to 461 nm. Dyes emit in yellow-blue region with emission maxima within 465 to 566 nm on excitation at their respective ICT absorption maxima. Moreover, compound 2, 3 and 9 exhibit aggregation induced emission in THF:water system due to the formation of nanoaggregates. Electrochemical properties of 2-10 were studied by cyclic voltammetry. The HOMO and LUMO energy level were found in the range of -4.90 to -5.70 eV and -3.10 to -3.36 eV respectively, with an electrochemical band gap (E g ) from 1.72 to 2.48 eV. Molecules showed good thermal stability. Theoretical studies were also carried out by using DFT and TD-DFT calculation. Based on photophysical and electrochemical properties these derivatives could be used as solid state emitter and ambipolar charge transport materials in optoelectronic devices.[a] S.

2-(Thienyl)quinoxaline derivatives and their application in Ir(iii) complexes yielding tuneable deep red emitters

“…In comparison, when a second thiophene ring was added to the quinoxaline sub-unit (L 10 H), a lower ε value (1.0 × 10 4 M −1 cm −1 ) at λ max 378 nm was recorded. It should be noted that previous studies have shown that charge transfer can be observed from the thiophene ring donors to the quinoxaline acceptors, 8 often explaining the observation of lower energy absorption bands. 29 L 1-11 H were analysed by steady state luminescence spectroscopy (Table 2, Fig.…”

“…We have sought to expand our repertoire of quinoxaline-containing ligands and considered the combination of the quinoxaline moiety with an electron rich thiophene-based donor component. There have been a small number of previous reports detailing the unique photophysical properties that result from the combination of thiophene and quinoxaline units in organic donor–acceptor (D–A) assemblies, 7 including compounds bearing a 2,3-di(thiophen-2-yl)quinoxaline core, 8 which displayed prominent intramolecular charge transfer (ICT) character. More recently, work on V-shaped D–A–D chromophores, where 1,5-thiophenylene acts as a π-conjugated spacer unit and either 6-cyano or 6,7-difluoroquinoxaline functioned as electron-acceptors have also been reported.…”

A Review on the Milestones of Blue Light-Emitting Materials in India

“…In addition, the HOMO and LUMO values were found in the range of −4.90 to 5.70 eV and −3.10 to −3.36 eV, respectively. 70 For the pyrene-substituted oxadiazole moiety, Najare et al developed a new molecule with proper hole and electron transfer (Figure 43). Differential scanning calorimetry and thermogravimetric analysis studies proved that the molecule has excellent stability for application in optoelectronics in the range of 204 -366 °C.…”

Synthesis and photophysical properties of quinoxaline-based blue aggregation-induced emission molecules

“…Previously, Tang's research group reported a series of pyrazine derivatives that show AIE feature due to push-pull electronic structure. 37 To further verify the AIE properties, the compounds 1-4 were dissolved in a good solvent (THF), and the ratio of poor solvent (water) was gradually increased. For example, compound 1 shows weak blue fluorescence in pure THF solution with the maximum emission peak of 413 nm (Fig.…”