Cu-catalysed direct C–H (hetero)arylation of [1,2,4]triazolo[4,3-a]pyridine to construct deep-blue-emitting luminophores

Jie Wu; Qiulin You; Jingbo Lan; Qiang Guo; Xiaoyu Li; Ying Xue; Jingsong You

doi:10.1039/c5ob00552c

2,7-Carbazole Derived Organoboron Compounds: Synthesis and Molecular Fluorescence

Frontiers in Chemistry ◽

10.3389/fchem.2021.754298 ◽

2021 ◽

Vol 9 ◽

Author(s):

Minhui Chen ◽

Juan Wei ◽

Yufeng Zhang ◽

Lin Wu ◽

Leibo Tan ◽

...

Keyword(s):

Solid State ◽

Electron Donor ◽

Electron Acceptor ◽

Blue Emission ◽

Luminescence Properties ◽

Quantum Yields ◽

Organoboron Compounds ◽

High Quantum ◽

Molecular Fluorescence ◽

State Luminescence

Triarylboranes have drawn much attention in OLEDs owing to their remarkable solid-state luminescence properties. Here two new A-D-A type compounds, 2,7-bis(dimesitylboryl)-N-ethyl-carbazole (BCz) using triarylborane as electron acceptor and carbazole as electron donor while 2,7-bis((4-(dimesitylboryl)phenyl)ethynyl)-9-ethyl-carbazole (BPACz) using phenylacetylene as extra conjugated bridge, have been synthesized and their photoluminescence related properties in various states have been investigated both experimentally and theoretically. Both compounds show blue emission with high quantum yields, being potential candidates for blue OLED materials.

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Conjugated copolymers bearing 2,7-dithienylphenanthrene-9,10-dialkoxy units: highly soluble and stable deep-blue emissive materials

New Journal of Chemistry ◽

10.1039/d0nj01712d ◽

2020 ◽

Vol 44 (22) ◽

pp. 9557-9564

Author(s):

Noorullah Baig ◽

Suchetha Shetty ◽

Sadiara Fall ◽

Saleh Al-Mousawi ◽

Thomas Heiser ◽

...

Keyword(s):

High Stability ◽

Blue Emission ◽

Quantum Yields ◽

Deep Blue ◽

Conjugated Copolymers

Excellent yields, high stability and solubility. Mw = 36.5–152.0 kDa and Đ = 2.5–3.0. Deep-blue emission with quantum yields up to 17%.

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Synthesis and optical and electrochemical properties of water-soluble cationic fluorophores based on bispyridinium and dibenzothiophene-S,S-dioxide

New Journal of Chemistry ◽

10.1039/c6nj03108k ◽

2017 ◽

Vol 41 (4) ◽

pp. 1696-1703 ◽

Cited By ~ 5

Author(s):

Guiting Chen ◽

Ruifeng He ◽

Wei Yang ◽

Bin Zhang

Keyword(s):

Electrochemical Properties ◽

Blue Emission ◽

Water Soluble ◽

Quantum Yields ◽

Deep Blue

Two water-soluble cationic fluorophores (FSOPyCl and FSOmiCl) based on bispyridinium and dibenzothiophene-S,S-dioxide show deep blue emission, and exhibit high photoluminescence quantum yields of 69% and 50% in water, respectively.

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Planar and Rigid Pyrazine Based TADF Emitter for Deep Blue Bright Organic Light Emitting Diodes

10.26434/chemrxiv.13626668 ◽

2021 ◽

Author(s):

P Rajamalli ◽

Dongyang Chen ◽

Subeesh Madayanad Suresh ◽

Youichi Tsuchiya ◽

Chihaya Adachi ◽

...

Keyword(s):

Dft Calculations ◽

Coupling Efficiency ◽

Blue Emission ◽

Delayed Fluorescence ◽

Quantum Yields ◽

Triplet States ◽

Light Emitting ◽

Thermally Activated ◽

Deep Blue ◽

Show Temperature Dependence

Two blue thermally activated delayed fluorescence (TADF) emitters bearing di-tert-butyl carbazoles as the electron donor groups and pyrazine (DTCz-Pz) or dipyrazine (DTCz-Pz) as the electron acceptor are presented. The DFT calculations predict DTCz-Pz and DTCz-DPz to possess high S1 energies (3.19 eV and 3.08 eV, respectively), and relatively large EST values (0.52 eV and 0.56 eV, respectively). The closely layered intermediate triplet states between S1 and T1, predicted by DFT calculations, are expected to facilitate the reverse intersystem crossing (RISC) and improve spin-vibronic coupling efficiency between the excited states even the relatively larger ΔESTs. The ΔESTs for DTCz-Pz and DTCz-DPz are 0.27 eV and 0.38 eV, and both molecules show high photoluminescence quantum yields (65%, and 70%, respectively) and the decay lifetimes show temperature dependence in a PPT host, which is consistent that both molecules are TADF emitters in PPT. The OLEDs based on DTCz-Pz exhibit deep blue emission with λEL of 460 nm and CIE of (0.15, 0.16). The maximum external quantum efficiency (EQEmax) reaches 11.6%, with a maximum luminance (Lmax) of up to 6892 cd m-2, while the device based on DTCz-DPz exhibits sky blue emission with λEL of 484 nm and CIE of (0.15, 0.30), an EQEmax of 7.2%, and Lmax of 8802 cd m-2.

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Design of highly efficient deep-blue organic afterglow through guest sensitization and matrices rigidification

Nature Communications ◽

10.1038/s41467-020-18572-9 ◽

2020 ◽

Vol 11 (1) ◽

Author(s):

Shen Xu ◽

Wu Wang ◽

Hui Li ◽

Jingyu Zhang ◽

Runfeng Chen ◽

...

Keyword(s):

High Performance ◽

Blue Emission ◽

High Energy ◽

Quantum Yields ◽

Stimuli Responsive ◽

Responsive Materials ◽

Organic Optoelectronics ◽

Deep Blue ◽

Formidable Challenge ◽

High Efficient

Abstract Blue/deep-blue emission is crucial for organic optoelectronics but remains a formidable challenge in organic afterglow due to the difficulties in populating and stabilizing the high-energy triplet excited states. Here, a facile strategy to realize the efficient deep-blue organic afterglow is proposed via host molecules to sensitize the triplet exciton population of guest and water implement to suppress the non-radiative decays by matrices rigidification. A series of highly luminescent deep-blue (405–428 nm) organic afterglow materials with lifetimes up to 1.67 s and quantum yields of 46.1% are developed. With these high-performance water-responsive materials, lifetime-encrypted rewritable paper has been constructed for water-jet printing of high-resolution anti-counterfeiting patterns that can retain for a long time (>1 month) and be erased by dimethyl sulfoxide vapor in 15 min with high reversibility for many write/erase cycles. These results provide a foundation for the design of high-efficient blue/deep-blue organic afterglow and stimuli-responsive materials with remarkable applications.

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New Base-Dopable Well-Defined Poly-2,7-Fluorene Derivatives

MRS Proceedings ◽

10.1557/proc-488-835 ◽

1997 ◽

Vol 488 ◽

Cited By ~ 1

Author(s):

M. Ranger ◽

M. Leclerc

Keyword(s):

Conjugated Polymers ◽

Blue Emission ◽

Polymeric Materials ◽

Quantum Yields ◽

Synthetic Method ◽

High Quantum ◽

Double Function ◽

Electrical Conductivities ◽

Palladium Catalyzed ◽

Polyfluorene Derivatives

AbstractWell-defined poly(2,7-fluorene) derivatives have been prepared through palladium-catalyzed couplings; using this versatile synthetic method, processable polyfluorenes have been obtained in good yields. In solution, these yellow polymers exhibit blue emission around 410 nm with high quantum yields. Moreover, novel acidic polyfluorene derivatives have been synthesized (e.g. poly(2,7'-(pentyl 9,9-dioctyl-7,2'-bifluorene-9'-carbonyl))) which show, upon base-doping, electrical conductivities of 10−2 − 10−3 S/cm. This new doping method for conjugated polymers could open the way to the preparation of air-stable electron-injecting electrodes. Polyfluorene derivatives show their potential to play a double function in the fabrication of LEDs, i.e. as ntype electrode and luminescent polymeric materials.

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Planar and Rigid Pyrazine Based TADF Emitter for Deep Blue Bright Organic Light Emitting Diodes

10.26434/chemrxiv.13626668.v1 ◽

2021 ◽

Author(s):

P Rajamalli ◽

Dongyang Chen ◽

Subeesh Madayanad Suresh ◽

Youichi Tsuchiya ◽

Chihaya Adachi ◽

...

Keyword(s):

Dft Calculations ◽

Coupling Efficiency ◽

Blue Emission ◽

Delayed Fluorescence ◽

Quantum Yields ◽

Triplet States ◽

Light Emitting ◽

Thermally Activated ◽

Deep Blue ◽

Show Temperature Dependence

Two blue thermally activated delayed fluorescence (TADF) emitters bearing di-tert-butyl carbazoles as the electron donor groups and pyrazine (DTCz-Pz) or dipyrazine (DTCz-Pz) as the electron acceptor are presented. The DFT calculations predict DTCz-Pz and DTCz-DPz to possess high S1 energies (3.19 eV and 3.08 eV, respectively), and relatively large EST values (0.52 eV and 0.56 eV, respectively). The closely layered intermediate triplet states between S1 and T1, predicted by DFT calculations, are expected to facilitate the reverse intersystem crossing (RISC) and improve spin-vibronic coupling efficiency between the excited states even the relatively larger ΔESTs. The ΔESTs for DTCz-Pz and DTCz-DPz are 0.27 eV and 0.38 eV, and both molecules show high photoluminescence quantum yields (65%, and 70%, respectively) and the decay lifetimes show temperature dependence in a PPT host, which is consistent that both molecules are TADF emitters in PPT. The OLEDs based on DTCz-Pz exhibit deep blue emission with λEL of 460 nm and CIE of (0.15, 0.16). The maximum external quantum efficiency (EQEmax) reaches 11.6%, with a maximum luminance (Lmax) of up to 6892 cd m-2, while the device based on DTCz-DPz exhibits sky blue emission with λEL of 484 nm and CIE of (0.15, 0.30), an EQEmax of 7.2%, and Lmax of 8802 cd m-2.

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Naphthalonitriles featuring efficient emission in solution and in the solid state

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.16.246 ◽

2020 ◽

Vol 16 ◽

pp. 2960-2970

Author(s):

Sidharth Thulaseedharan Nair Sailaja ◽

Iván Maisuls ◽

Jutta Kösters ◽

Alexander Hepp ◽

Andreas Faust ◽

...

Keyword(s):

Excited State ◽

Photophysical Properties ◽

Aqueous Media ◽

Blue Emission ◽

Blue Shift ◽

Red Shift ◽

Quantum Yields ◽

Structure Property ◽

Time Resolved ◽

Deep Blue

In this work, a series of γ-substituted diphenylnaphthalonitriles were synthesized and characterized. They show efficient emission in solution and in the aggregated state and their environment responsiveness is based on having variable substituents at the para-position of the two phenyl moieties. The excited state properties were fully investigated in tetrahydrofuran (THF) solutions and in THF/H2O mixtures. The size of the aggregates in aqueous media were measured by dynamic light scattering (DLS). The steady-state and time-resolved photoluminescence spectroscopy studies revealed that all the molecules show intense fluorescence both in solution and in the aggregated state. In THF solutions, a blue emission was observed for the unsubstituted (H), methyl- (Me) and tert-butyl- (t-Bu) substituted γ-diphenylnaphthalonitriles, which can be attributed to a weak π-donor capability of these groups. On the other hand, the methoxy- (OMe), methylsulfanyl- (SMe) and dimethylamino- (NMe2) substituted compounds exhibit a progressive red-shift in emission compared to H, Me and t-Bu due to a growing π-electron donating capability. Interestingly, upon aggregation in water-containing media, H, Me and t-Bu show a slight red-shift of the emission and a blue-shift is observed for OMe, SMe and NMe2. The crystal structure of Me allowed a detailed discussion of the structure–property relationship. Clearly, N-containing substituents such as NMe2 possess more electron-donating ability than the S-based moieties such as SMe. Moreover, it was found that NMe2 showed higher luminescence quantum yields (ΦF) in comparison to SMe, indicating that N-substituted groups could enhance the fluorescence intensity. Therefore, the π-donor nature of the substituents on the phenyl ring constitutes the main parameter that influences the photophysical properties, such as excited state lifetimes and photoluminescence quantum yields. Hence, a series of highly luminescent materials from deep blue to red emission depending on substitution and environment is reported with potential applications in sensing, bioimaging and optoelectronics.

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Luminescent tetraphenylethene-substituted silanes

Pure and Applied Chemistry ◽

10.1351/pac-con-09-09-15 ◽

2010 ◽

Vol 82 (4) ◽

pp. 863-870 ◽

Cited By ~ 17

Author(s):

Zujin Zhao ◽

Shuming Chen ◽

Jacky W. Y. Lam ◽

Carrie Y. K. Chan ◽

Cathy K. W. Jim ◽

...

Keyword(s):

Thin Films ◽

Thermal Stability ◽

Weight Loss ◽

High Thermal Stability ◽

Quantum Yields ◽

Maximum Luminance ◽

Amorphous Films ◽

Fluorescence Quantum Yields ◽

Deep Blue ◽

High Fluorescence

Tetraphenylethene (TPE)-substitued silanes [(Ph4C=C)mSi(Ph)n, m = 3–1, n = 3–1] are designed and synthesized, and their optical, thermal, and electrochemical properties are studied. Whereas they are nonluminescent in solutions, they become highly emissive when aggregated in poor solvents (such as water) or fabricated into thin films, demonstrating a novel phenomenon of aggregation-induced emission (AIE). Their amorphous films exhibit high fluorescence quantum yields (54.6–63.7 %). They enjoy high thermal stability with 5 % weight loss occurring at 320–420 °C. Multilayer electroluminescence (EL) devices (ITO/NPB/emitter/TPBi/LiF/Al) utilizing the silanes as emitting layers are fabricated, which give deep blue EL with maximum luminance and external quantum efficiency of 5672 cd/m2, and 1.6 %, respectively.

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