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1.
Organic Crystals with Near‐Infrared Amplified Spontaneous Emissions Based on 2′‐Hydroxychalcone Derivatives: Subtle Structure Modification but Great Property Change 下载免费PDF全文
Xiao Cheng Kai Wang Shuo Huang Dr. Houyu Zhang Prof. Dr. Hongyu Zhang Prof. Dr. Yue Wang 《Angewandte Chemie (International ed. in English)》2015,54(29):8369-8373
A series of highly efficient deep red to near‐infrared (NIR) emissive organic crystals 1 – 3 based on the structurally simple 2′‐hydroxychalcone derivatives were synthesized through a simple one‐step condensation reaction. Crystal 1 displays the highest quantum yield (Φf) of 0.32 among the reported organic single crystals with an emission maximum (λem) over 710 nm. Comparison between the bright emissive crystals 1 – 3 and the nearly nonluminous compounds 4 – 7 clearly gives evidence that a subtle structure modification can arouse great property changes, which is instructive in designing new high‐efficiency organic luminescent materials. Notably, crystals 1 – 3 exhibit amplified spontaneous emissions (ASE) with extremely low thresholds. Thus, organic deep red to NIR emissive crystals with very high Φf have been obtained and are found to display the first example of NIR fluorescent crystal ASE. 相似文献
2.
Dr. Naruyoshi Komiya Nao Itami Prof. Takeshi Naota 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(29):9497-9505
Morphology control for intense solid‐state phosphorescence of non‐emissive, but potentially emissive crystals of platinum complexes and the mechanistic rationale are described. A series of trans‐bis(salicylaldiminato)platinum(II) complexes bearing linear alkyl chains ( 1 a : n=5; 1 b : n=8; 1 c : n=12; 1 d : n=14; 1 e : n=16; 1 f : n=18) was synthesized and the solid‐state emission properties were examined by using crystals/aggregates prepared under various precipitation conditions. Crystals of 1 e , prepared using “kinetic” conditions including rapid cooling, high concentrations, and poor solvents, emit intensive yellow phosphorescence (λmax=545 nm) under UV irradiation at 298 K with an absolute quantum efficiency of 0.36, whereas all the crystals of 1 a – 1 f prepared using “thermodynamic” conditions including slow cooling, low concentrations, and good solvents were either non‐ or less emissive with Φ298K values of 0.12 ( 1 a ), 0.11 ( 1 b ), 0.10 ( 1 c ), 0.07 ( 1 d ), 0.02 ( 1 e ), and 0.02 ( 1 f ) under the same measurement conditions. The amorphous solid 1 e , prepared by rapid cooling and freeze‐drying, was also non‐emissive (Φ298K=0.02, 0.02). Temperature‐dependent emission spectra showed that the kinetic crystals of 1 e exhibit high heat‐resistance towards emission decay with increasing temperature, whereas the amorphous solid 1 e is entirely heat‐quenchable. This is a rare example of the change from a non‐emissive crystal into a highly emissive crystal by morphology control through crystal engineering. Emission spectra and powder X‐ray diffraction (XRD) patterns of the emissive, kinetic crystals of 1 e are clearly distinct from those of the less emissive, thermodynamic crystals of 1 a – 1 f . Single‐crystal XRD unequivocally establishes that the thermodynamic crystals of 1 d have a multilayered lamellar structure supported by highly regulated, consecutive π‐stacking interactions between imine moieties, whereas the kinetic crystals of 1 e have a face‐to‐edge lamellar structure with less stacking. These results lead to the conclusion that 1) morphology control of long‐chained complexes exclusively generates a metastable herringbone‐based lamellar packing motif that exhibits intense emission and high heat‐resistance, while 2) a thermodynamically stable, highly regulated, consecutive stacking motif is unfavorable for solid‐state emission. 相似文献
3.
Gavin Coombs Marcus H. Sak Prof. Scott J. Miller 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(7):2897-2902
We have demonstrated that small, modular, tetrameric peptides featuring the Lewis-basic residue β-dimethylaminoalanine (Dmaa) are capable of atroposelectively coupling naphthols and ester-bearing quinones to yield non-C2-symmetric BINOL-type scaffolds with good yields and enantioselectivity. The study culminates in the asymmetric synthesis of backbone-substituted scaffolds similar to 3,3′-disubstituted BINOLs, such as (R)-TRIP, with good (94:6 e.r.) to excellent (>99.9:0.1 e.r.) enantioselectivity after recrystallization, and a diastereoselective net arylation of the minimally modified nonsteroidal anti-inflammatory drug (NSAID) naproxen. 相似文献
4.
Sungwoo Kim Prof. Jean Bouffard Prof. Youngmi Kim 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(48):17459-17465
4,4‐Difluoro‐4‐bora‐3a,4a‐diaza‐s‐indacene (BODIPY) derivatives bearing varied substituents at the meso position (i.e., CF3, CH3, COOR, CHO, CN, Cl, iPr) were synthesized to elucidate the structure–property relationships that give rise to emissive J‐aggregates. Several new BODIPY derivatives can be added to the previously reported 1,3,5,7‐tetramethyl‐8‐trifluoromethyl derivative to the list of those forming J‐aggregates, in addition to other dyes that are emissive in the solid state without forming J‐aggregates. 相似文献
5.
Lindsey L. Johnston Andrew J. Ursini Nathan P. Oien Matthew P. Desciak Randy S. Rarig Jr. Jon Zubieta Robert L. LaDuca Prof. 《无机化学与普通化学杂志》2008,634(5):887-891
Hydrothermal treatment of aqueous mixtures of copper(II) halides and 3,3′‐bipyridine (3,3′‐bpy) has afforded the coordination polymers [CuCl(3,3′‐bpy)]n ( 1 ) and [Cu2Br2(3,3′‐bpy)]n ( 2 ), which were analyzed via single crystal X‐ray diffraction, infrared spectroscopy, and elemental analysis. The structure of 1 consists of two‐dimensional (2‐D) layers constructed from the linkage of castellated one‐dimensional (1‐D) [CuCl]n stepped chains through anti‐conformation 3,3′‐bpy tethers. Compound 2 presents a related 2‐D sheet motif, albeit built from infinite 1‐D [Cu2Br2]n ladders strutted by 3,3′‐bpy ligands in anti conformation. In both cases neighboring 2‐D sheets stack into 3‐D via weak C–H···halogen interactions. 相似文献
6.
Gavin Coombs Marcus H. Sak Scott J. Miller 《Angewandte Chemie (International ed. in English)》2020,59(7):2875-2880
We have demonstrated that small, modular, tetrameric peptides featuring the Lewis‐basic residue β‐dimethylaminoalanine (Dmaa) are capable of atroposelectively coupling naphthols and ester‐bearing quinones to yield non‐C2‐symmetric BINOL‐type scaffolds with good yields and enantioselectivity. The study culminates in the asymmetric synthesis of backbone‐substituted scaffolds similar to 3,3′‐disubstituted BINOLs, such as (R)‐TRIP, with good (94:6 e.r.) to excellent (>99.9:0.1 e.r.) enantioselectivity after recrystallization, and a diastereoselective net arylation of the minimally modified nonsteroidal anti‐inflammatory drug (NSAID) naproxen. 相似文献
7.
《中国化学会会志》2017,64(6):574-588
This review is aimed at the current research progression of a unique class of Pt(II ) metal complexes bearing at least one azolate‐containing bidentate chelate. The azole fragment can link to a neutral heteroaromatic entity or another azole and form bidentate chelates, such as monoanionic 3‐pyridyl‐1H ‐pyrazole and derivatives, dianionic 3,3′‐bi‐1H ‐pyrazole, 3,3′‐(1‐methylethylidene)‐bis‐1H ‐pyrazole, and their analogs. These azole‐containing chelates readily react with a variety of Pt(II) reagents to afford the corresponding bis‐bidentate Pt(II) complexes. Most of them were highly emissive in solution, doped polymer matrix, thin film, and even as crystal or powder, due to the high ligand field strength exerted by these chelates and their high propensity in forming the singular square‐planar architecture and intermolecular aggregates with substantially strengthened Pt⋯Pt interaction, according to their structural design. Therefore, they hold bright prospects in academic research and future optoelectronic applications such as organic light‐emitting diodes. 相似文献
8.
Krishnayan Basuroy Appavu Rajagopal Dr. Srinivasarao Raghothama Prof. Narayanaswamy Shamala Prof. Padmanabhan Balaram 《化学:亚洲杂志》2012,7(7):1671-1678
The effect of gem‐dialkyl substituents on the backbone conformations of β‐amino acid residues in peptides has been investigated by using four model peptides: Boc‐Xxx‐β2,2Ac6c(1‐aminomethylcyclohexanecarboxylic acid)‐NHMe (Xxx=Leu ( 1 ), Phe ( 2 ); Boc=tert‐butyloxycarbonyl) and Boc‐Xxx‐β3,3Ac6c(1‐aminocyclohexaneacetic acid)‐NHMe (Xxx=Leu ( 3 ), Phe ( 4 )). Tetrasubstituted carbon atoms restrict the ranges of stereochemically allowed conformations about flanking single bonds. The crystal structure of Boc‐Leu‐β2,2Ac6c‐NHMe ( 1 ) established a C11 hydrogen‐bonded turn in the αβ‐hybrid sequence. The observed torsion angles (α(?≈?60°, ψ≈?30°), β(?≈?90°, θ≈60°, ψ≈?90°)) corresponded to a C11 helical turn, which was a backbone‐expanded analogue of the type III β turn in αα sequences. The crystal structure of the peptide Boc‐Phe‐β3,3Ac6c‐NHMe ( 4 ) established a C11 hydrogen‐bonded turn with distinctly different backbone torsion angles (α(?≈?60°, ψ≈120°), β(?≈60°, θ≈60°, ψ≈?60°)), which corresponded to a backbone‐expanded analogue of the type II β turn observed in αα sequences. In peptide 4 , the two molecules in the asymmetric unit adopted backbone torsion angles of opposite signs. In one of the molecules, the Phe residue adopted an unfavorable backbone conformation, with the energetic penalty being offset by a favorable aromatic interaction between proximal molecules in the crystal. NMR spectroscopy studies provided evidence for the maintenance of folded structures in solution in these αβ‐hybrid sequences. 相似文献
9.
Helicenes as All‐in‐One Organic Materials for Application in OLEDs: Synthesis and Diverse Applications of Carbo‐ and Aza[5]helical Diamines 下载免费PDF全文
Samik Jhulki Abhaya Kumar Mishra Prof. Dr. Tahsin J. Chow Prof. Dr. Jarugu Narasimha Moorthy 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(27):9375-9386
A set of eight helical diamines were designed and synthesized to demonstrate their relevance as all‐in‐one materials for multifarious applications in organic light‐emitting diodes (OLEDs), that is, as hole‐transporting materials (HTMs), EMs, bifunctional hole transporting + emissive materials, and host materials. Azahelical diamines function very well as HTMs. Indeed, with high Tg values (127–214 °C), they are superior alternatives to popular N,N′‐di(1‐naphthyl)‐N,N′‐diphenyl‐(1,1′‐biphenyl)‐4,4′‐diamine (NPB). All the helical diamines exhibit emissive properties when employed in nondoped as well as doped devices, the performance characteristics being superior in the latter. One of the carbohelical diamines (CHTPA) serves the dual function of hole transport as well as emission in simple double‐layer devices; the efficiencies observed were better by quite some margin than those of other emissive helicenes reported. The twisting endows helical diamines with significantly high triplet energies such that they also function as host materials for red and green phosphors, that is, [Ir(btp)2acac] (btp=2‐(2′‐benzothienyl)pyridine; acac=acetylacetonate) and [Ir(ppy)3] (ppy=2‐phenylpyridine), respectively. The results of device fabrications demonstrate how helicity/ helical scaffold may be diligently exploited to create molecular systems for maneuvering diverse applications in OLEDs. 相似文献
10.
Photochromic 6‐bromomethyl‐6′‐methyl‐[2,2′‐bi‐1H‐indene]‐3,3′‐diethyl‐3,3′‐dihydroxy‐1,1′‐dione ( 2 ), 6,6′‐ bis(bromomethyl)‐[2,2′‐bi‐1H‐indene]‐3,3′‐diethyl‐3,3′‐dihydroxy‐1,1′‐dione ( 3 ) and 6,6′‐bis(dibromomethyl)‐[2,2′‐ bi‐1H‐indene]‐3,3′‐diethyl‐3,3′‐dihydroxy‐1,1′‐dione ( 4 ) have been synthesized from 6,6′‐dimethyl‐[2,2′‐bi‐1H‐ indene]‐3,3′‐diethyl‐3,3′‐dihydroxy‐1,1′‐dione ( 1 ). The single crystal of 4 was obtained and its crystal structure was analyzed. The results indicate that in crystal 4 , molecular arrangement is defective tightness compared with its precursor 1 . Besides, UV‐Vis absorption spectra in CH2Cl2 solution, photochromic and photomagnetic properties in solid state of 2 , 3 and 4 were also investigated. The results demonstrate that when the hydrogen atoms in the methyl group on the benzene rings of biindenylidenedione were substituted by bromines, its properties could be affected considerably. 相似文献
11.
Long Yin Junhao Xing Yuhan Wang Yue Shen Tao Lu Tamio Hayashi Xiaowei Dou 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(8):2496-2500
The enantioselective synthesis of a series of C2‐symmetric 3,3′‐diarylated 1,1′‐spirobiindane‐7,7′‐diols (3,3′‐diaryl‐SPINOLs) was developed by sequential Rh‐catalyzed twofold asymmetric conjugate arylation/BF3‐promoted diastereoselective spirocyclization (>20:1 d.r. and >99 % ee for all examples). Some phosphoramidite ligands were prepared from the 3,3′‐Ph‐SPINOL and applied to several catalytic asymmetric reactions, and the 3,3′‐diarylated ligands showed higher enantioselectivities than the privileged nonsubstituted ligands. 相似文献
12.
《Journal of Coordination Chemistry》2012,65(18):3136-3145
Coordination polymers of CuII and NiII with 3-pyridin-3-yl-benzoic acid (3,3-Hpybz), {[Cu(3,3-pybz)2(CH3OH)]·(DMF)} n (1) and {[Ni(3,3-pybz)2(H2O)]?·?(H2O)} n (2), were synthesized and characterized by single-crystal X-ray diffraction, thermogravimetric analyses, elemental analysis, and IR spectroscopy. In 1, CuII ions are linked by paired 3,3-pybz ligands to generate an in?nite 1-D double-strand chain. However, NiII ions in 2 are linked by the 3,3-pybz to form a 2-D corrugated network with a simple (4,4) topology; these 2-D layers are further enlarged to form the final 3-D supramolecular edifice via strong aromatic π–π stacking interactions and O–H?···?O hydrogen bonds. Magnetic properties of 1 and 2 have also been investigated. 相似文献
13.
3,3′-Thiobispyridine is prepared by reaction of pyridine-3-thiol with 3-bromopyridine. The base peak in the mass spectrum of 3,3′-thiobispyridine is due to the molecular ion which fragments by loss of H, HCN and CS as well as by central bond rupture. The 1,1′-dimethyl diquaternary salt of 3,3′-thiobispyridine is reduced polarographically by a one electron transfer not involving hydrogen to an unstable radical cation at a potential (Eo) of −0.72 V in the pH range 7.4–11.2. 相似文献
14.
María I. García Trimio Anthony Linden Heinz Heimgartner Arturo Macías Cabrera 《Helvetica chimica acta》1993,76(8):2817-2829
Reaction of N-acyl-3,3-diamino-2-nitroacrylthioamides 1 with MeI at room temperature leads to N-acyl-S-methyl-3,3-diamino-2-nitroacrylthioimidates 2 in moderate yields. The latter react with Hg(OAc)2 in DMF yielding 3-(acylamino)-3-amino-2-nitroacrylonitriles 8 . The structures of 2a and 8a were established by X-ray crystallography. 相似文献
15.
Jianlei Han Dong Yang Xue Jin Yuqian Jiang Minghua Liu Pengfei Duan 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(21):7087-7093
Achieving a large dissymmetry factor (glum) is a challenge in the field of circularly polarized luminescence (CPL). A chiral charge‐transfer (CT) system consisting of chiral electron donor and achiral electron acceptor shows bright circularly polarized emission with large glum value. The chiral emissive CT complexes could be fabricated through various approaches, such as grinding, crystallization, spin coating, and gelatinization, by simply blending chiral donor and achiral acceptor. The structural synergy originating from π–π stacking and strong CT interactions resulted in the long‐range ordered self‐assembly, enabling the formation of supramolecular gels. Benefiting from the large magnetic dipole transition moment in the CT state, the CPL activity of CT complexes exhibited large circular polarization. Our design strategy of the chiral emissive CT complexes is expected to help the development of new molecular engineering strategies for designing highly efficient CPL‐active materials. 相似文献
16.
Estimation of Critical Temperature of Thermal Explosion for Nitrosubstituted Azetidines Using Non-isothermal DSC 总被引:1,自引:0,他引:1
Based on reasonable hypothesis, two general expressions and their six derived formulae for estimating the critical temperature (Tb) of thermal explosion for energetic materials (EM) were derived from the Semenov's thermal explosion theory and eight non‐isothermal kinetic equations. We can easily obtain the values of the initial temperature (T0i) at which DSC curve deviates from the baseline of the non‐isothermal DSC curve of EM, the onset temperature (Tei), the exothermic decomposition reaction kinetic parameters and the values of T00 and Te0 from the equation T0i or ei=T00 or e0+a1βi+a2βi2+···+aL?2βiL?2, i=1, 2, ;···, L and then calculate the values of Tb by the six derived formulae. The Tb values for seven nitrosubstituted azetidines, 3,3‐dinitroazetidinium nitrate ( 1 ), 3,3‐dinitroazetidinium picrate ( 2 ), 3,3‐dinitroazetidinium‐3‐nitro‐1,2,4‐triazol‐5‐onate ( 3 ), 1,3‐bis(3′,3′‐dinitroazetidine group)‐2,2‐dinitropropane ( 4 ), 1‐(2′,2′,2′‐trinitroethyl)‐3,3‐dinitroazetidine ( 5 ), 3,3‐dinitroazetidinium perchlorate ( 6 ) and 1‐(3′,3′‐dinitroazetidineyl)‐2,2‐dinitropropane ( 7 ), obtained with the six derived formulae are agreeable to each other, whose differences are within 1.5%. The results indicate that the heat‐resistance stability of the seven nitrosubstituted azetidines decreases in the order 6 > 7 > 5 > 4 > 3 > 2 > 1 . 相似文献
17.
Kyle T. Smith Kye Hunter Nan-Chieh Chiu Hao Zhuang Peemapat Jumrusprasert William F. Stickle Jeffrey A. Reimer Tim J. Zuehlsdorff Kyriakos C. Stylianou 《Angewandte Chemie (International ed. in English)》2023,62(25):e202302123
Luminescent materials with tunable emission are becoming increasingly desirable as we move towards needing efficient Light Emitting Diodes (LEDs) for displays. Key to developing better displays is the advancement of strategies for rationally designing emissive materials that are tunable and efficient. We report a series of emissive metal-organic frameworks (MOFs) generated using BUT-10 (BUT: Beijing University of Technology) that emits green light with λmax at 525 nm. Post-synthetic reduction of the ketone on the fluorenone ligand in BUT-10 generates new materials, BUT-10-M and BUT-10-R. The emission for BUT-10-R is hypsochromically-shifted by 113 nm. Multivariate BUT-10-M structures demonstrate emission with two maxima corresponding to the emission of both fluorenol and fluorenone moieties present in their structures. Our study represents a novel post-synthetic ligand reduction strategy for producing emissive MOFs with tunable emission ranging from green, white-blue to deep blue. 相似文献
18.
Jingling Yan Taihang Li Zhen Wang Lianxun Gao Mengxian Ding 《Journal of polymer science. Part A, Polymer chemistry》2007,45(21):4933-4940
3,3′‐Dichloro‐N,N′‐biphthalimide (3,3′‐DCBPI), 3,4′‐dichloro‐N,N′‐biphthalimide (3,4′‐DCBPI), and 4,4′‐dichloro‐N,N′‐biphthalimide (4,4′‐DCBPI) were synthesized from 3‐ or 4‐chlorophthalic anhydrides and hydrazine in glacial acetic acid. The yield of 3,3′‐DCBPI (90%) was much higher than that of 4,4′‐DCBPI (33%) because of the better stability of the intermediate, 3‐chloro‐N‐aminophthalimide, and 3,3′‐DCBPI. A series of hydrazine‐based polyimides were prepared from isomeric DCBPIs and 4,4′‐thiobisbenzenethiol (TBBT) in N,N‐dimethylacetamide in the presence of tributylamine. Inherent viscosity of these polymers was in the range of 0.51–0.69 dL/g in 1‐methyl‐2‐pyrrolidinone (NMP) at 30 °C. These polyimides were soluble in 1,1,2,2‐terachloroethane, NMP, and phenols. The 5% weight‐loss temperatures (T5%s) of the polymers were near 450 °C in N2. Their glass‐transition temperatures (Tgs) determined by dynamic mechanical thermal analysis and differential scanning calorimetry increased according to the order of polyimides based on 4,4′‐DCBPI, 3,4′‐DCBPI, and 3,3′‐DCBPI. The hydrolytic stability of these polymers was measured under acid, basic, and neutral conditions and the results indicated that the order was 3,3′‐DCBPI/TBBT > 3,4′‐DCBPI/TBBT > 4,4′‐DCBPI/TBBT. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4933–4940, 2007 相似文献
19.
Ryusuke Hagihara Dr. Tomohiro Umeno Dr. Shoji Ueki Dr. Daisuke Yoshihara Dr. Yasufumi Fuchi Dr. Kazuteru Usui Masaomi Sakuma Prof. Dr. Ken-ichi Yamada Prof. Dr. Satoru Karasawa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(9):3039-3046
Emissive push–pull-type bisnaphthyridylamine derivatives ( BNA-X : X=Me, Et, Bzl, Ph, BuBr, and BuTEMPO) aggregate in aqueous methanol. Furthermore, a two-step emission and aggregation process is controllable by varying the methanol-to-water ratio. At 2:3 MeOH/H2O, crystallization-induced emission enhancement (CIEE) occurs via formation of an emissive crystal phase, whereas, at 1:9 MeOH/H2O, aggregation-induced emission enhancement (AIEE) occurs, induced by emissive supramolecular nanoparticles (NPs). For BNA-Ph , the emission quantum yield was 25 times higher in aqueous methanol than that in pure methanol. Despite the high hydrophobicity of BNA-X (C log P=6.1–8.0), the spherical NPs were monodisperse (polydispersity indices <0.2). Moreover, the emissive NPs exhibited fluorescence resonance energy transfer (FRET) with pyrene; however, for BNA-X bearing the TEMPO radical ( BNA-BuTEMPO ), no FRET was observed because of quenching. In particular, the BNA-BuTEMPO NPs have a slow rotational correlation time (1.3 ns), suggesting applications as magnetic resonance imaging contrast agents with large relaxivity. 相似文献
20.
Shiao‐Wen Hwang Shinn‐Horng Chen Yun Chen 《Journal of polymer science. Part A, Polymer chemistry》2002,40(14):2215-2224
Four novel poly(aryl ether)s ( P1 – P4 ) consisting of alternate isolated electron‐transporting (3,3″′‐bis‐trifluoromethyl‐p‐quaterphenyl for P1 , P3 or 3,3″′‐dicyano‐p‐quaterphenyl for P2 , P4 ) and hole‐transporting fluorophores [N‐(2‐ethylhexyl)‐3,6‐bis(styryl)carbazole for P1 , P2 or 9,9‐dihexyl‐2,7‐bis(styryl)fluorene for P3 , P4 ] were synthesized and characterized. These poly(aryl ether)s can be dissolved in organic solvents and exhibited good thermal stability with 5% weight‐loss temperature above 500 °C in nitrogen atmosphere. The photoluminescent (PL) spectra of the films of these polymers showed maximum peaks at around 442–452 nm. The PL spectral results revealed that the emission of polymers was dominated by the fluorophores with longer emissive wavelength via the energy transfer from p‐quaterphenyl to 3,6‐bis(styryl)carbazole or 2,7‐bis(styryl)fluorene segments. Therefore, the p‐quaterphenyl segments function only as the electron‐transporting/hole‐blocking units in these polymers, and the other segments are the emissive centers and hole‐transporting units. The highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital energy levels of these polymers were measured by cyclic voltammetry. The electron‐donating nitrogen atom on carbazole resulted in the higher HOMO energy levels of P1 and P2 than those of P3 and P4 . The single‐layer light‐emitting diodes (LED) of Al/poly(aryl ether)s ( P1 – P4 )/ITO glass were fabricated. P1 , P2 , and P4 revealed blue electroluminescence, but P3 emitted yellow light as a result of the excimer emission. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2215–2224, 2002 相似文献