N,O π-Conjugated 4-Substituted 1,3-Thiazole BF₂ Complexes: Synthesis and Photophysical Properties

Abstract

A series of 1,3-thiazole-based organoboron complexes has been designed and synthesized by acylation of 2-amino 4-subsituted 1,3-thiazoles with (4-dimethylamino)benzoyl chloride and the subsequent BF complexation reaction. The influence of substituents in position 4 of the thiazole ring on photophysical properties of the complexes has been investigated. Synthesized thiazolo[3,2-c][1,3,5,2]oxadiazaborinines mainly showed intensive fluorescence in solutions. Complex with a 4,5-unsubstituted thiazole unit demonstrated an aggregation induced emission (AIE) effect and a very high fluorescent quantum yield (94%) in the solid state because of the inhibition of π-π/π-n interactions in the molecular packing.

Retracted Article: Facile preparation of bithiazole-based material for inkjet printed light-emitting electrochemical cell

“…In this context, p-p intermolecular interactions can inhibit the uorescence. 48 It may indicate that enlarging the conjugation length and electron density with these donor groups plays an important role in increasing the f PL . 49 Moreover, those with high f PL may be suitable for application as efficient light-emitting material in LECs.…”

“…53 This difference probably accounts for the high concentration of donor units in the bithiazole backbone, low rates of intersystem crossing to reactive triplet states. 48,54 Consequently, the composite 1c was the best performing LEC and chosen for the below test. The EL spectra obtained for both devices were almost identical, with a main peak at 498 nm and other peak at 504 nm wavelength as illustrated in Fig.…”

2‐(2‐Hydroxyphenyl)‐5‐aminothiazoles: Synthesis and Properties Involving Dual Emissions

“…As recent examples (Figure ), thiazole I showed an aggregation‐induced emission effect . Thiazole II was developed as a photoluminescent probe for selective determination of the concentration of protein kinase CK2 .…”

Synthesis and Characterization of Oxazaborinin Phosphonate for Blue OLED Emitter Applications

“…[6] Although, boron complexes with N,N-chelating ligands (e. g. BODIPYs) are well investigated and widely used as fluorescent dyes, their less investigated N,O-analogues are becoming increasingly important because of their stronger emission in solid state. [18][19][20][21][22][23] Compared to widely used N,O-ligands, such as 8-hydroxyquinolines, pyridylphenolates have a less conjugated system which results in blue emission (hypsochromic effect). [24] Indeed, only few blue emitters of four-coordinate boron with pyridylphenolate ligands have been reported in the literature [25,26] and additional investigations are needed.…”

“…The structures of the boron‐bridged molecules are π‐conjugated and can easily be tuned for desirable properties by modifying the chelating ligand or substituent on boron . Although, boron complexes with N,N‐chelating ligands (e. g. BODIPYs) are well investigated and widely used as fluorescent dyes, their less investigated N,O‐analogues are becoming increasingly important because of their stronger emission in solid state . Compared to widely used N,O‐ligands, such as 8‐hydroxyquinolines, pyridylphenolates have a less conjugated system which results in blue emission (hypsochromic effect) .…”