- Synthesis and charge-transfer complex formations of 1,n-bis(3,6- diethylcarbazol-9-yl)alkanes with three π-acceptors
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Dimeric 1,n-bis(3,6-diethylcarbazol-9-yl)alkanes (where n = 1-5) were synthesized and their structures were characterized via spectroscopic techniques. Structures of two of the dimers, 1,2-bis(3,6-diethylcarbazol-9-yl) ethane (2b) and 1,4-bis(3,6-diethylcarbazol-9-yl)butane (2d), were investigated by single crystal X-ray crystallographic techniques. The crystal structures of 2b and 2d were solved in the monoclinic space groups C2/c and P21/n, respectively. The methylene chain adopted an anti conformation in 2b and a gauche-anti-gauche conformation in 2d, enabling coplanar orientations of carbazole rings in both structures. The molecular packing in both structures was stabilized by intermolecular π-π stacking. Charge transfer complexations of 2a-2e with the π-acceptors p-chloranil, tetracyanoethylene, and tetracyanoquinodimethane in solution were investigated by determining their stoichiometries, molar absorptivities, equilibrium constants, enthalpies, and entropies. All the dimers formed weakly associated complexes with each of the acceptors having equilibrium constants between 1.32-8.94 M-1 in 1,2-dichloroethane. Complexations were driven by the slightly negative formation enthalpies between -2.00 and -4.24 kcal mol-1.
- Asker, Erol,Filiz, Fahrettin
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- A novel carbazole-based fluorescent probe: 3,6-Bis-[(N-ethylcarbazole-3-yl)-propene-1-keto]-N-ethylcarbazole
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A novel carbazole-based compound 5, 3,6-bis[(N-ethylcarbazole-3-yl)-propene-1-keto]-N-ethylcarbazole has been designed, synthesized and characterized. The absorption and fluorescence spectra in solvents of different polarities prove that the compound has a distinct intramolecular charge transfer character. Compound 5 can be used as a new class of fluorescent probe or biosensor due to its sensitivity to the local microenvironment such as solvent polarity.
- Hao, Li Ling,Li, Jun Fen,Lin, Pei Hua,Dong, Rui Feng,Li, Du Xin,Shuang, Shao Min,Dong, Chuan
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- Synthesis, photophysics, electrochemistry, thermal stability and electroluminescent performances of a new europium complex with bis(β-diketone) ligand containing carbazole group
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We synthesized a new europium complex [Eu(ecbpd)3(Phen)] with bis(β-diketone) ligand containing a carbazole group, in which ecbpd and Phen are dehydro-3,3′-(9-ethyl-9H-carbazole-3,6-diyl)bis(1-phenylpropane-1,3-dione) and 1,10-phenanthroline, respectively. Its UV/vis and photoluminescent spectra, quantum yield, luminescence lifetime, electrochemistry, thermal stability and electroluminescent performances were studied. This europium complex showed low efficiency luminescence, which is probably due to the mismatching energy levels of its ligand and Eu3 +, as well as the double Eu3 + core resonance.
- Liu, Jian,Liang, Quan-Bin,Wu, Hong-Bin
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- Carbazole-containing difluoroboron β-diketonate dyes: Two-photon excited fluorescence in solution and grinding-induced blue-shifted emission in the solid state
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Mechanochromic luminescent (MCL) materials have attracted considerable attention in recent years because of their potential applications in various fields and the fundamental importance of understanding the mechanism of mechanochromic luminescence. The most reported MCL materials show a bathochromic shift after external mechanical stimulus. Here we report new MCL materials with hypochromic shift of the emission after grinding. These materials are based on carbazole-containing difluoroboron β-diketonate complexes. These complexes show strong fluorescence in both the solid state and organic solutions. Our study reveals that the emission of structural symmetrical complexes is less influenced by the polarity of the solvent than those of unsymmetrical complexes and they retain strong fluorescence in highly polar solvents. In addition, the good planarity of the carbazole group and the ICT character of the complexes make them exhibit obvious two-photon excited fluorescence. In the solid state, their emission colours can be tuned reversibly by external stimuli, and they exhibit an unusual hypochromic shift after grinding. Single crystal X-ray analysis of the complexes reveals that the initial close molecular packing is responsible for the blue-shifted emission. Interestingly, both hypsochromic and bathochromic shifts of the emission are realized by different treatments of the samples. Our work provides information on the mechanism of the mechanochromic luminescent properties of organic luminescent materials and expands the potential applications of MCL materials.
- Chen, Peng-Zhong,Wang, Jian-Xin,Niu, Li-Ya,Chen, Yu-Zhe,Yang, Qing-Zheng
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- A Green Synthesis of 2-Amino-4-(9H-carbazole-3-yl)thiophene-3-carbonitriles by a Step-wise and One-pot Three-component Gewald Reaction
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An eco-friendly method has been developed for the synthesis of 2-amino-4-(9H-carbazole-3-yl)thiophene-3-carbonitriles from preliminary carbazole (1) through an intermediate of 2-(1-(9H-carbazole-3-yl)ethylidene)malononitriles using the Knoevenagel condensation followed by the Gewald reaction. On the other hand, the target compounds could also be prepared in a one-pot three-component manner by treating equimolar quantities of 1-(9H-carbazole-3-yl)ethanone (3), malononitrile, and elemental sulfur. The merits of this preparation are mild reaction conditions. The Gewald reaction is executed with inorganic base NaHCO3 (H2O) in tetrahydrofuran, easy work-up procedure with good yields.
- Avula, Vijay Kumar Reddy,Vallela, Swetha,Anireddy, Jaya Shree,Chamarthi, Naga Raju
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- Synthesis and Optical Properties of New Chalcones Containing a 3,4-Ethylenedioxythiophene Fragment
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Abstract: A new series of chalcones bearing two or more 3,4-ethylenedioxythiophene fragments were synthesized, and their optical properties were studied. The Stokes shifts (Δλ) and band gaps (Egopt) were calculated on the basis of the absorption and emission spectra. The largest Stokes shift (115 nm) was found for a symmetrical product of the terephthalaldehyde and 3,4-ethylenedioxythiophene-2-carbaldehyde condensation, and the smallest band gap (1.93 eV) is characteristic of a chalcone that contains a 2,2',5',2''-ter(3,4-ethylenedioxythiophene). Correlations were established between the band gap and mutual arrangement of the 3,4-ethylenedioxythiophene fragments in the prepared chalcones.
- Ignashevich,Shavrina,Shklyaeva,Abashev
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p. 1920 - 1928
(2021/01/13)
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- Design and synthesis of aryl-functionalized carbazole-based porous coordination cages
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A subset of coordination cages have garnered considerable recent attention for their potential permanent porosity in the solid state. Herein, we report a series of functionalized carbazole-based cages of the structure type M12(R-cdc)12 (M = Cr, Cu, Mo) where the functional groups include a range of aromatic substituents. Single-crystal X-ray structure determinations reveal a variety of intercage interactions in these materials, largely governed by pi-pi stacking. Density functional theory for a subset of these cages was used to confirm that the nature of the increased stability of aryl-functionalized cages is a result of inter-cage ligand interactions. This journal is
- Rowland, Casey A.,Lorzing, Gregory R.,Bhattacharjee, Rameswar,Caratzoulas, Stavros,Yap, Glenn P. A.,Bloch, Eric D.
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supporting information
p. 9352 - 9355
(2020/10/02)
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- Synthesis and luminescence properties of nine novel carbazolyl diacylhydrazone Schiff-bases
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Nine novel carbazolyl diacylhydrazone Schiff-bases were synthesized by alkylation, F-C acylation and condensation reactions starting from carbazole and hydrazide. The title Schiff-bases were characterized by 1H NMR, MS, IR and elemental analysis. The synthetic conditions were optimized, and the best yield of the title Schiff-bases was up to 92.3%. The relationships between the luminescence properties and the structures of the title Schiff-bases were studied. The results showed that the introduction of the Naphthalene-2-yloxy could form great plane conjugate structure to improve their luminescence properties.
- Wu, Limin,Wu, Panliang,Guo, Dongcai,Fu, Wenqiang,Li, Dong,Luo, Tao
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- Bipolar luminescent materials containing pyrimidine terminals: Synthesis, photophysical properties and a theoretical study
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A new series of 4-monosubstituted pyrimidine bipolar materials containing a carbazole (PM1-PM2) or a triphenylamine (PM3-PM5) moiety as the electron donor have been synthesized by a ZnCl2-catalyzed three-component coupling reaction. These 4-monosubstituted pyrimidine compounds were characterized by UV-vis and fluorescence spectroscopy, cyclic voltammetry, as well as density functional theory (DFT) calculations. It was intriguing to find that these 4-monosubstituted pyrimidine compounds exhibited bright fluorescence with excellent quantum yields (~0.53-0.93) in the blue region. PM1 and PM2 had a lower LUMO than that of CBP (4,4-di(9H-carbazol-9-yl)biphenyl), meaning that both of them had better electron injection and transfer abilities. The variation tendencies of energy levels and absorption spectra obtained from DFT calculations agreed well with those from experiment. Other electronic properties including ionization potentials (IP), electronic affinities (EA), and reorganization energies (λhole and λ electron) have been theoretically studied as well. These electronic properties could be tuned by introducing a different number of pyrimdin-4-yl moieties onto to the donor fragments. The incorporation of pyrimdin-4-yl can significantly decrease the λelectron and then improve the electron-accepting and hole-electron charge balance abilities. The combined theoretical and experimental studies offer insights into the nature of bipolar molecules containing 4-monosubstituted pyrimidine moieties, and provided a fertile ground for the design of appropriate ambipolar materials for optoelectronic applications. The Royal Society of Chemistry 2013.
- Weng, Jiena,Mei, Qunbo,Fan, Quli,Ling, Qidan,Tong, Bihai,Huang, Wei
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p. 21877 - 21887
(2013/11/06)
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- Dendritic Photoactive Compound Comprising Oxime Ester And Method For Preparing The Same
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The present invention relates to a dendritic photoactive compound that comprises oxime ester and a method for producing the same. Since the compound according to the present invention comprises two or more oxime ester groups and chromophores in one molecu
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Page/Page column 7
(2010/06/19)
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- Synthesis of a novel β-diketone containing carbazole and 2,5-diphenyl-1,3,4-oxadiazole fragments
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A novel β-diketone containing carbazole and 2,5-diphenyl-1,3,4- oxadiazole fragments as hole- and electron-transporting functional groups, respectively, was synthesized via efficient and convenient procedure. The product attracts interest from the viewpoint of its potential applications as optoelectronic material.
- Tang, Huaijun,Zhang, Zhiguo,Cong, Changjie,Zhang, Keli
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p. 559 - 563
(2009/09/06)
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- DENDRITIC PHOTOACTIVE COMPOUND COMPRISING OXIME ESTER AND METHOD FOR PREPARING THE SAME
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The present invention relates to a dendritic photoactive compound that comprises oxime ester and a method for producing the same. Since the compound according to the present invention comprises two or more oxime ester groups and chromophores in one molecu
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Page/Page column 14-15
(2009/03/07)
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- A convenient synthesis of 3,6-substituted carbazoles via nickel catalyzed cross-coupling
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Alkyl, vinyl and aryl substitiuted carbazoles at the 3- and 6-positions are prepared in high yield from the corresponding 3,6-dibromocarbazole via nickel catalyzed coupling with Grignard reagents (Corriu-Kumada coupling).
- Park, Minnie,Buck, Jason R.,Rizzo, Carmelo J.
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p. 12707 - 12714
(2007/10/03)
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