Synthesis, electronic structure, linear and nonlinear photophysical properties of novel asymmetric branched compounds

Functionalized 1,3,5-triazine derivatives as components for photo- and electroluminescent materials

“…Cai et al presented a series of novel asymmetric single-branched ( 136 , 137 ), double-branched ( 138 , 139 ), and triple-branched ( 140 , 141 ) compounds with 1,3,5-triazine core (Fig. 54); 90 carbazole (or phenothiazine) and pyridine (or benzimidazole) were selected as the peripheral electron donor and acceptor, respectively, and the electron-donating methoxy groups were introduced in the middle of the branch as the auxiliary donors. All derivatives were obtained by sequential condensation of 2,4,6-trimethyl-1,3,5-triazine with corresponding aldehydes; photophysical properties, including linear absorption, one-photon excited fluorescence (OPEF), two-photon absorption, and frequency up-converted fluorescence, of compounds 136–141 were studied in different solvents.…”

“…Obtained results 90 allowed the authors to conclude that the compounds 136–141 do not exhibit a strong cooperative effect associated with the non-additive enhancement of σ . Based on the σ values of 139 and 141 (787–2072 GM), which are much larger than those of the analogous compounds 138 and 140 (328–844 GM), it seems reasonable to infer that the benzimidazole acceptor could be a very useful TPA structural unit.…”

I2/H2O2 mediated synthesis and photophysical properties of imidazole-fused heterocycles via [4+1] cyclization approach

“…Specifically, applications of imidazo [1,5a]pyridines and benzimidazoles in organic optoelectronic materials include organic light-emitting devices (OLEDs) [30,31], nonlinear optic materials (NLOs) [32,33], photosensitizers based on organic metal complexes [34,35], fluorescence cell imaging [36,37], organic fluorescent probes [38][39][40][41][42], sensors and emitters for confocal microscopy [17] and so on. In the design of fluorescent dyes and fluorescent materials, introducing strong electron donors and extending the molecular π-conjugated system has been proven to be an efficient strategy to lengthen emission wavelengths as well as Stokes shifts [43][44][45][46][47][48] Besides, fluorescent dyes with electron donors can retain a relatively high fluorescent quantum yield, which is determined by the gap between frontier orbitals [49][50][51][52][53].…”

Electronic Absorption, Emission, and Two-Photon Absorption Properties of Some Extended 2,4,6-Triphenyl-1,3,5-Triazines

“…Thus far, emissive triphenyl-s-triazine derivatives and related extended analogues have mainly raised interest in the field of OLEDs or closely related fields [15][16][17][18]; however, very few studies were actually focused on the NLO properties of such derivatives. While related derivatives such as extended trialkynyl-s-triazines [19], trialkenyl-s-triazines [20,21], or tris(2-thienyl)-s-triazines [22][23][24][25] have given rise to some 2PA investigations, to the best of our knowledge, only one recent theoretical paper deals specifically with the second-order NLO properties of molecules such as 3-X [26], and only one other single paper addresses the 2PA properties of an s-triazine derivative closely related to 7-H [27]. Thus, regarding extended triphenyl-s-triazines, essentially styryl-type analogues of 3-X have been investigated so far for their 2PA properties [28][29][30].…”