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

1997 ◽  
Vol 488 ◽  
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.

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

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.

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

2015 ◽  
Vol 13 (19) ◽  
pp. 5372-5375 ◽  
Author(s):  
Jie Wu ◽  
Qiulin You ◽  
Jingbo Lan ◽  
Qiang Guo ◽  
Xiaoyu Li ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Blue Emission ◽  
Quantum Yields ◽  
High Quantum ◽  
Deep Blue

An efficient protocol for the synthesis of 3-aryl-[1,2,4]triazolo[4,3-a]pyridines has been developed via Cu-catalysed direct C–H (hetero)arylation. The resulting compounds exhibit deep-blue emission with high quantum yields, photostability, and thermal stability.

Synthesis and fluorescence study of conjugated polymers based on 2,4,6-triphenylpyridine moieties

2016 ◽  
Vol 40 (7) ◽  
pp. 6281-6288 ◽  
Author(s):  
Qianping Ran ◽  
Jianfeng Ma ◽  
Tao Wang ◽  
Shimin Fan ◽  
Yong Yang ◽  
...  
Keyword(s):  
Conjugated Polymers ◽  
Fluorescence Emission ◽  
Band Gaps ◽  
Quantum Yields ◽  
Fluorescence Study ◽  
Strong Fluorescence ◽  
High Quantum ◽  
Stokes Shifts

Three novel 2,4,6-triphenylpyridine-based conjugated polymers showed strong fluorescence emission with large Stokes' shifts, tunable band gaps and high quantum yields.

Electronic structure studies of conducting polymers by electron energy-loss spectroscopy

1996 ◽  
Vol 54 ◽  
pp. 160-161
Author(s):  
J. Fink
Keyword(s):  
Electronic Structure ◽  
Conducting Polymers ◽  
Conjugated Polymers ◽  
Electron Acceptors ◽  
Electron Donors ◽  
Light Emitting ◽  
One Dimensional ◽  
New Class ◽  
Electrical Conductivities ◽  
Electron Energy Loss

Conducting polymers comprises a new class of materials achieving electrical conductivities which rival those of the best metals. The parent compounds (conjugated polymers) are quasi-one-dimensional semiconductors. These polymers can be doped by electron acceptors or electron donors. The prototype of these materials is polyacetylene (PA). There are various other conjugated polymers such as polyparaphenylene, polyphenylenevinylene, polypoyrrole or polythiophene. The doped systems, i.e. the conducting polymers, have intersting potential technological applications such as replacement of conventional metals in electronic shielding and antistatic equipment, rechargable batteries, and flexible light emitting diodes.Although these systems have been investigated almost 20 years, the electronic structure of the doped metallic systems is not clear and even the reason for the gap in undoped semiconducting systems is under discussion.

scholarly journals Selective Synthesis of N-Acylnortropane Derivatives in Palladium-Catalysed Aminocarbonylation

Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1813
Author(s):  
László Kollár ◽  
Ádám Erdélyi ◽  
Haroon Rasheed ◽  
Attila Takács
Keyword(s):  
Synthetic Method ◽  
Selective Synthesis ◽  
Varied Structure ◽  
Biological Importance ◽  
Aryl Iodides ◽  
Palladium Catalyzed ◽  
Derivatives Of

The aminocarbonylation of various alkenyl and (hetero)aryl iodides was carried out using tropane-based amines of biological importance, such as 8-azabicyclo[3.2.1]octan-3-one (nortropinone) and 3α-hydroxy-8-azabicyclo[3.2.1]octane (nortropine) as N-nucleophile. Using iodoalkenes, the two nucleophiles were selectively converted to the corresponding amide in the presence of Pd(OAc)2/2 PPh3 catalysts. In the presence of several iodo(hetero)arenes, the application of the bidentate Xantphos was necessary to produce the target compounds selectively. The new carboxamides of varied structure, formed in palladium-catalyzed aminocarbonylation reactions, were isolated and fully characterized. In this way, a novel synthetic method has been developed for the producing of N-acylnortropane derivatives of biological importance.

Regioselective Oxidative Cross-Coupling Reaction: Synthesis of Imidazo[1,2-a]pyridine Fluorophores

Synthesis ◽  
2021 ◽  
Author(s):  
Xianglong Chu ◽  
Yadi Niu ◽  
Chen Ma ◽  
Xiaodong Wang ◽  
Yunliang Lin ◽  
...  
Keyword(s):  
Photophysical Properties ◽  
Coupling Reaction ◽  
Cross Coupling ◽  
Quantum Yields ◽  
Fluorescence Quantum Yields ◽  
Cross Coupling Reaction ◽  
Color Tunable ◽  
Palladium Catalyzed ◽  
Structure Relationship ◽  
High Fluorescence

AbstractA rapid access to a series of N-heteroarene fluorophores has been developed on the basis of the palladium-catalyzed direct oxidative C–H/C–H coupling of imidazo[1,2-a]pyridines with thiophenes/furans. The photophysical properties–structure relationship was systematically investigated. The resulting N-heteroarene fluorophores present color-tunable emissions (λem: 431–507 nm in CH2Cl2) and high fluorescence quantum yields (up to 91% in CH2Cl2).

scholarly journals Backbone Effects on the Thermoelectric Properties of Ultra-Small Bandgap Conjugated Polymers

Polymers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 2486
Author(s):  
Dexun Xie ◽  
Jing Xiao ◽  
Quanwei Li ◽  
Tongchao Liu ◽  
Jinjia Xu ◽  
...  
Keyword(s):  
Conjugated Polymers ◽  
Power Factor ◽  
Carrier Mobility ◽  
Polymeric Materials ◽  
Thermoelectric Performance ◽  
Organic Thermoelectric Materials ◽  
Higher Power ◽  
Donor Acceptor ◽  
Maximum Power Factor ◽  
Higher Carrier Mobility

Conjugated polymers with narrower bandgaps usually induce higher carrier mobility, which is vital for the improved thermoelectric performance of polymeric materials. Herein, two indacenodithiophene (IDT) based donor–acceptor (D-A) conjugated polymers (PIDT-BBT and PIDTT-BBT) were designed and synthesized, both of which exhibited low-bandgaps. PIDTT-BBT showed a more planar backbone and carrier mobility that was two orders of magnitude higher (2.74 × 10−2 cm2V−1s−1) than that of PIDT-BBT (4.52 × 10−4 cm2V−1s−1). Both exhibited excellent thermoelectric performance after doping with 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane, where PIDTT-BBT exhibited a larger conductivity (0.181 S cm−1) and a higher power factor (1.861 μW m−1 K−2) due to its higher carrier mobility. The maximum power factor of PIDTT-BBT reached 4.04 μW m−1 K−2 at 382 K. It is believed that conjugated polymers with a low bandgap are promising in the field of organic thermoelectric materials.

scholarly journals Synthesis of π-Conjugated Polymers Containing Benzotriazole Units via Palladium-Catalyzed Direct C-H Cross-Coupling Polycondensation for OLEDs Applications

Polymers ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 254
Author(s):  
Dong Han ◽  
Jingwen Li ◽  
Qiang Zhang ◽  
Zewang He ◽  
Zhiwei Wu ◽  
...  
Keyword(s):  
Conjugated Polymers ◽  
Quantum Efficiency ◽  
Cross Coupling ◽  
Building Blocks ◽  
Gravimetric Analysis ◽  
19F Nmr Spectra ◽  
Light Emitting ◽  
Molecular Weights ◽  
Palladium Catalyzed ◽  
Red Luminescence

Four D-π-A conjugated polymers, namely P1–P4, which contain benzotriazole building blocks in their backbone as acceptor, are synthesized via palladium-catalyzed direct C-H cross-coupling polycondensation of 5,6-difluorobenzotriazole with different thiophene derivatives, including 3-octylthiophene, 2,2’-bithiophene, thieno[3,4-b][1,4]dioxine, and 4,4-dioctyl-4H-silolo-[3,2-b:4,5-b’]dithiophene as donor units, respectively. Taking the polymer P1 as an example, the chemical structure of the polymer is demonstrated by 1H and 19F NMR spectra. The optical, electrochemical, and thermal properties of these polymers are assessed by UV–vis absorption and fluorescence spectroscopy, cyclic voltammetry (CV), and thermal gravimetric analysis (TGA), respectively. DFT simulations of all polymers are also performed to understand their physicochemical properties. Furthermore, P1 and P2, which have relatively higher molecular weights and better fluorescent quantum efficiency than those of P3 and P4, are utilized as lighting emitters for organic light-emitting diodes (OLEDs), affording promising green and red luminescence with 0.07% and 0.14% of maximum external quantum efficiency, respectively, based on a device with an architecture of ITO/PEDOT:PSS/PTAA/the polymer emitting layer/TPBi/LiF/Al.

Highly efficient orange-red electroluminescence of iridium complexes with good electron mobility

2017 ◽  
Vol 5 (32) ◽  
pp. 8150-8159 ◽  
Author(s):  
Hua-Bo Han ◽  
Rong-Zhen Cui ◽  
Yi-Ming Jing ◽  
Guang-Zhao Lu ◽  
You-Xuan Zheng ◽  
...  
Keyword(s):  
Current Efficiency ◽  
Electron Mobility ◽  
Quantum Yields ◽  
Iridium Complexes ◽  
Maximum Luminance ◽  
High Quantum ◽  
Highly Efficient ◽  
Maximum Current ◽  
Low Efficiency

Two orange-red iridium complexes with high quantum yields and good electron mobility were applied in efficient OLEDs showing a maximum luminance of 129 466 cd m−2, a maximum current efficiency of 62.96 cd A−1 with low efficiency roll-off.

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