Synthesis, Photophysical and Redox Properties of the D–π–A Type Pyrimidine Dyes Bearing the 9-Phenyl-9H-Carbazole Moiety

Abstract

Novel donor-π-acceptor dyes bearing the pyrimidine unit as an electron-withdrawing group have been synthesized by using combination of two processes, based on the microwave-assisted Suzuki cross-coupling reaction and nucleophilic aromatic substitution of hydrogen. Spectral properties of the obtained dyes in six aprotic solvents of various polarities have been studied by ultraviolet-visible and fluorescence spectroscopy. In contrast to the absorption spectra, fluorescence emission spectra displayed a strong dependence from their solvent polarities. The nature of the observed long wavelength maxima has been elucidated by means of quantum chemical calculations. The electrochemical properties of these dyes have been investigated by using cyclic voltammetry, while their photovoltaic performance was evaluated by a device fabrication study. The experimental and calculation data show that all of the dyes can be regarded as potentially good photosensitizers for dye-sensitized solar cells.

Detection of nitroaromatic explosives by new D–π–A sensing fluorophores on the basis of the pyrimidine scaffold

“…As continuation of our previous studies aimed at obtaining of (hetero)arylated bithio-phenes and their analogues as photosensitizers for dye-sensitized solar cells [17,22,23], and being inspired by the results reported by other groups concerning optical materials based on pyrimidinetriphenylamine and pyrimidine-carbazole dyads [24][25][26][27][28], we have focused our attention on using of donor-π-acceptor Electronic supplementary material The online version of this article (doi:10.1007/s00216-016-9501-4) contains supplementary material, which is available to authorized users. organic dyes, bearing pyrimidine fragments, as chemosensors for NACs.…”

“…The excitation and emission spectra of the dyes were measured in various solvents [22,23], and fluorescence quenching studies were carried out in acetonitrile. For each analyte, the typical test procedure was as follows: 2.5 mL of acetonitrile solution of one of the fluorophores (1.0 × 10 −5 mol/L) was drawn and placed in a quartz cell of the standard size.…”

“…For all pyrimidine derivatives studied, the structures of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) have been calculated in the framework of the density functional theory (DFT) at the B3LYP/6-311G(d,p) level in a suite of Gaussian 09 programs [22,23]. In order to get an insight into the quenching mechanism, quantum-chemical computations on photo-physical properties of 1a and its interaction with DNT have been performed by using the ORCA3.0.3 [29] program package.…”

New V-shaped push-pull systems based upon 4,5-di(hetero)aryl substituted pyrimidines: their synthesis and application for the detection of nitroaromatic explosives

“…[39][40][41] Also some pyrimidines exhibit second order nonlinear optical properties. 42,43 In continuation of our previous studies on (hetero)aryl substituted bithiophenes and their analogues, as photosensitizers for dye-sensitized solar cells, 22,23,44 and taking into account the results reported by other groups on the use of pyrimidine-triphenylamine and pyrimidine-carbazole dyads in optical materials, 35,36 we have focused our attention on donor-π-acceptor organic dyes bearing the pyrimidine fragment, as chemosensors for nitroaromatic explosives. In this communication we report the synthesis of pyrimidine-based V-shaped new organic fluorophores with yellow-green emission, their photophysical properties and sensitivity towards nitroaromatics.…”

“…Thanks to the presence of highly delocalized π-electronic systems, these molecules have found wide applications in organic light-emitting diodes (OLEDs), nonlinear optics, dye-sensitized solar cells and field-effect transistors (FETs). [13][14][15][16][17][18][19][20][21][22][23][24][25][26] Furthermore, triphenylamine and carbazolebased compounds are used successfully as sensors for the detection of nitroaromatic explosives. [27][28][29][30][31] Oligothiophenes and their derivatives have also been employed successfully as sensing elements for detection of explosives.…”