New luminescent tetracoordinate boron complexes: an in-depth experimental and theoretical characterisation and their application in OLEDs

Abstract

A group of new tetracoordinate mononuclear 2-(N-phenylformimino)pyrrolyl boron chelates [BX2{κ2N,N’-NC4H3-2-C(H)=N-C6H5}] (X=F 3; mesityl (2,4,6-trimethylphenyl, Mes) 4; C6F55; X2=1,1'-biphenyl-2,2'-di-yl 6) and the related binuclear complex [(C6F5)2B{κ2N,N’-NC4H3-2-C(H)=N-C6H4-N=C(H)-C4H3N-κ2N,N’}B(C6F5)2] 7 were synthesised via...

Red-Emitting Tetraphenylethylene-Based Boron Thioketonates: Effect of Substitution and Study of Nonlinear Optical Properties

“…Boron-containing luminescent materials, − especially four-coordinated boron-containing luminescent materials, − have attracted considerable interest in various fields such as photovoltaics, organic field-effect transistors, light-emitting devices, and sensors owing to their tuneable and strong absorption, emission and stability over three-coordinated boron compounds. − Among the different tetracoordinated boron-containing luminescent materials, boron-β-diketonates have been studied to a greater extent due to their large molar extinction coefficients and high fluorescence quantum yields. Much effort has been paid to tune the photophysical properties of boron-β-diketonates by chemically modifying the π-conjugation via the substituents. ,− For example, Fraser and co-workers explored the substituent effect of boron-β-diketonates and studied them as stimuli-responsive materials, , and Chujo and co-workers described the effect of B–F vs B–aryl. , More recently, Adachi and co-workers demonstrated the use of boron-β-diketonates as NIR emissive materials. , Furthermore, efforts have been made to tune the photophysical properties by replacing one or two of the oxygen atoms present in the diketone moiety.…”

Synthesis, photophysical properties, bioimaging potential andin vitrotoxicity studies of naphthalimide imidazole boron complexes

“…Tetra-coordinated boron complexes are a class of materials that have gained attention owing to their greater stability over tri-coordinated boron complexes and wide applications in biological as well as optoelectronic devices. 1–4 Possible ways of obtaining various tetra-coordinated boron complexes with the desired properties are tuning the ligand with different chelates (N,N-; N,O-; N,C-; O,O-; etc. ) and (or) changing the substituents on the boron atom.…”

Luminescent hexagonal microtubes prepared through water-induced self-assembly of a polymorphic organoboron compound: formation mechanism and waveguide behaviour

“…27 The B-O and B-N bonds of such TCOB molecules have a greater covalent character compared to the B-F bond found in the BODIPy class of fluorophores. 28,29 Specifically, tetra-coordinated organoboron (TCOB) compounds with extended π-conjugation and structural rigidity exhibit notable Stokes shifts, improved fluorescence emission (both in solid and solution states) and offer a broad range of molecular diversity through chemical synthesis. 30 Hydroxyquinolate, 31,32 pyridylphenolate, 33,34 benzimidazolephenolate, 35 and similar bidentate heterocyclic ligands are often used to prepare TCOB complexes.…”