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1.
The purposeful modulation of the optoelectronic properties was realised on the basis of a series of the large, conjugated, phosphine oxide hosts 9,9‐bis‐{4′‐[2‐(diphenylphosphinoyl)phenoxy]biphenyl‐4‐yl}‐9H‐fluorene (DDPESPOF), 9,9‐bis‐{3′‐(diphenylphosphinoyl)‐4′‐[2‐(diphenylphosphinoyl)phenoxy]biphenyl‐4‐yl}‐9H‐fluorene (DDPEPOF), 9‐[4′‐(9‐{4′‐[2‐(diphenylphosphoryl)phenoxy]biphenyl‐4‐yl}‐9H‐fluoren‐9‐yl)biphenyl‐4‐yl]‐9H‐carbazole (DPESPOFPhCz) and 9‐[4′‐(9‐{3′‐(diphenylphosphoryl)‐4′‐[2‐(diphenylphosphoryl)phenoxy]biphenyl‐4‐yl}‐9H‐fluoren‐9‐yl)biphenyl‐4‐yl]‐9H‐carbazole (DPEPOFPhCz). The last two are quaternary with fluorenyls as linking bridges, diphenylphosphine oxide (DPPO) moieties as electron acceptors and diphenylethers and carbazolyls as two different kinds of electron donors. Owing to the fine‐organised molecular structures and the mixed indirect and multi‐insulating linkages, all of these hosts achieve the same first triplet energy levels (T1) of 2.86 eV for exothermic energy transfer to phosphorescent dopants. The first singlet energy levels (S1) and the carrier injection/transportation ability of the hosts were accurately modulated, so that DPESPOFPhCz and DPEPOFPhCz revealed extremely similar optoelectronic properties. However, the T1 state of the former is localised on fluorenyl, whereas the carbazolyl mainly contributes to the T1 state of the latter. A lower driving voltages and much higher efficiencies of the devices based on DPESPOFPhCz indicated that the chromophore‐localised T1 state can suppress the quenching effects through realising independent contributions from the different functional groups to the optoelectronic properties and the embedding and protecting effect on the T1 states by peripheral carrier transporting groups.  相似文献   

2.
A new liquid crystalline (LC) acceptor monomer 2,5‐bis[4‐(4′‐cyanobiphenyloxy)dodecyl]‐3,6‐dithiophen‐2‐yl‐pyrrolo[3,4‐c]pyrrole‐1,4‐dione (TDPPcbp) was synthesized by incorporating cyanobiphenyl mesogens into diketopyrrolopyrrole (DPP). The monomer was copolymerized with bis(2‐ethylhexyloxy)benzo[1,2‐b:4,5‐b′] dithiophene (BDT) and N‐9′‐heptadecanylcarbazole (CB) donors to obtain donor–acceptor alternating copolymers poly[4,8‐bis(2‐ethylhexyloxy)benzo[1,2‐b:4,5‐b′]dithiophene‐alt‐3,6‐bis(thiophen‐5‐yl)‐2,5‐bis[4‐(4′‐cyanobiphenyloxy)dodecyl]‐2,5‐dihydropyrrolo[3,4‐c]pyrrole‐1,4‐dione] (PBDTDPPcbp) and poly[N‐9′‐heptadecanyl‐2,7‐carbazole‐alt‐3,6‐bis(thiophen‐5‐yl)‐2,5‐bis[4‐(4′‐cyano‐biphenyloxy)dodecyl]‐2,5‐dihydropyrrolo[3, 4‐c]pyrrole‐1,4‐dione] (PCBTDPPcpb) with reduced band gap, respectively. The LC properties of the copolymers, the effects of main chain variation on molecular packing, optical properties, and energy levels were analyzed. Incorporating the mesogen cyanobiphenyl units not only help polymer donors to pack well through mesogen self‐organization but also push the fullerene acceptor to form optimized phase separation. The bulk heterojunction photovoltaicdevicesshow enhanced performance of 1.3% for PBDTDPPcbp and 1.2% for PCBTDPPcbp after thermal annealing. The results indicate that mesogen‐controlled self‐organization is an efficient approach to develop well‐defined morphology and to improve the device performance. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013  相似文献   

3.
The reaction of 1H‐indol‐2,3‐diones with 1,6‐dibromohexane has resulted in the formation of new 1H‐indol‐2,3‐diones‐1,1′‐(1,6‐hexanediyl)bis in quantitative yields. These compounds have been used for the synthesis of novel [3′‐(2,3‐dimethyl‐5‐oxo‐1‐phenyl‐3‐pyrazolin‐4‐yl)spiro[3H‐indol‐3,2′‐thiazolidine]‐2,4′‐dione]‐1,1′‐(1,6‐hexanediyl)bis via bis Schiff's bases, [3‐(2,3‐dimethyl‐5‐oxo‐1‐phenyl‐3‐pyrazolin‐4‐yl) imino‐1H‐indol‐2‐one]‐1,1′‐(1,6‐hexanediyl)bis.  相似文献   

4.
A two‐dimensional MnII coordination polymer (CP), poly[bis[μ2‐2,6‐bis(imidazol‐1‐yl)pyridine‐κ2N3:N3′]bis(thiocyanato‐κN)manganese] [Mn(NCS)2(C11H9N5)2]n, (I), has been obtained by the self‐assembly reaction of Mn(ClO4)2·6H2O, NH4SCN and bent 2,6‐bis(imidazol‐1‐yl)pyridine (2,6‐bip). CP (I) was characterized by FT–IR spectroscopy, elemental analysis and single‐crystal X‐ray diffraction. The crystal structure features a unique two‐dimensional (4,4) network with one‐dimensional channels. The luminescence and nitrobenzene‐sensing properties were explored in a DMF suspension, revealing that CP (I) shows a strong luminescence emission and is highly sensitive for nitrobenzene detection.  相似文献   

5.
Two noble metal complexes involving ancillary chloride ligands and chelating 2,2′‐bipyridylamine (Hdpa) or its deprotonated derivative (dpa), namely [bis(pyridin‐2‐yl‐κN)amine]tetrachloridoplatinum(IV), [PtCl4(C10H9N3)], and [bis(pyridin‐2‐yl‐κN)aminido]dichloridogold(III), [AuCl2(C10H8N3)], are presented and structurally characterized. The metal atom in the former has a slightly distorted octahedral coordination environment, formed by four chloride ligands and two pyridyl N atoms of Hdpa, while the metal atom in the latter has a slightly distorted square‐planar coordination environment, formed by two chloride ligands and two pyridyl N atoms of dpa. The difference in conjugation between the pyridine rings in normal and deprotonated 2,2′‐dipyridylamine is discussed on the basis of the structural features of these complexes. The influence of weak interactions on the supramolecular structures of the complexes, providing one‐dimensional chains of [PtCl4(C10H9N3)] and dimers of [AuCl2(C10H8N3)], are discussed.  相似文献   

6.
A mixture of an isocyanide and dibenzoylacetylene in dry CH2Cl2 undergoes a smooth addition reaction at ambient temperature to furnish 3‐[5‐(alkylimino)‐3,4‐dibenzoyl‐2‐phenylfuran‐2(2H)‐yl]‐ 1‐phenylprop‐2‐yn‐1‐ones (1 : 2 adduct) and {2,5‐bis(alkylimino)‐4,7,8a‐triphenyl‐5H‐difuro[2,3‐b:3′,4′‐e]pyran‐3(8aH)‐yl}(phenyl)methanones (2 : 2 adduct). Single‐crystal X‐ray analyses conclusively confirmed the structures of the adducts.  相似文献   

7.
Four 2,2′‐bisindolylmethanes (BIMs), a useful class of polyindolyl species joined to a central carbon, were synthesized using salicylaldehyde derivatives and simple acid catalysis; these are 2‐[bis(3‐methyl‐1H‐indol‐2‐yl)methyl]‐6‐methylphenol, (IIa), 2‐[bis(3‐methyl‐1H‐indol‐2‐yl)methyl]‐4,6‐dichlorophenol, (IIb), 2‐[bis(3‐methyl‐1H‐indol‐2‐yl)methyl]‐4‐nitrophenol, (IIc), and 2‐[bis(3‐methyl‐1H‐indol‐2‐yl)methyl]‐4,6‐di‐tert‐butylphenol, (IId). BIMs (IIa) and (IIb) were characterized crystallographically as the dimethyl sulfoxide (DMSO) disolvates, i.e. C26H24N2O·2C2H6OS and C25H20Cl2N2O·2C2H6OS, respectively. Both form strikingly similar one‐dimensional hydrogen‐bonding chain motifs with the DMSO solvent molecules. BIM (IIa) packs into double layers of chains whose orientations alternate every double layer, while (IIb) forms more simply packed chains along the a axis. BIM (IIa) has a remarkably long c axis.  相似文献   

8.
The unsymmetrical N‐heterocyclic ligand 1‐[(benzotriazol‐1‐yl)methyl]‐1H‐1,3‐imidazole (bmi) has three potential N‐atom donors and can act in monodentate or bridging coordination modes in the construction of complexes. In addition, the bmi ligand can adopt different coordination conformations, resulting in complexes with different structures due to the presence of the flexible methylene spacer. Two new complexes, namely bis{1‐[(benzotriazol‐1‐yl)methyl]‐1H‐1,3‐imidazole‐κN 3}dibromidomercury(II), [HgBr2(C10H9N5)2], and bis{1‐[(benzotriazol‐1‐yl)methyl]‐1H‐1,3‐imidazole‐κN 3}diiodidomercury(II), [HgI2(C10H9N5)2], have been synthesized through the self‐assembly of bmi with HgBr2 or HgI2. Single‐crystal X‐ray diffraction shows that both complexes are mononuclear structures, in which the bmi ligands coordinate to the HgII ions in monodentate modes. In the solid state, both complexes display three‐dimensional networks formed by a combination of hydrogen bonds and π–π interactions. The IR spectra and PXRD patterns of both complexes have also been recorded.  相似文献   

9.
Two novel electropolymerizable monomers, namely 3,5‐bis(4‐diphenylaminobenzamido)‐N‐[4‐(carbazol‐9‐yl)phenyl]benzamide ( 5 ) and 3,5‐bis(4‐diphenylaminobenzamido)‐N‐[4‐(3,6‐dimethoxycarbazol‐9‐yl)phenyl]benzamide ( 5‐MeO ), were synthesized, and their electrochemical properties were studied by cyclic voltammetry. The electron‐withdrawing amide groups efficiently blocked the radical cations delocalization between the two terminal TPA groups, rendering the electropolymerization of the TPA groups feasible. The polymer electrodeposited from monomer 5 could be further crosslinked through electro‐coupling of the carbazole groups, which showed both electrochromic and fluorescent properties (the emission of blue light (460 nm) in solid state). Both of the electro‐generated polymer films derived from 5 and 5‐MeO showed reversible electrochemical oxidation processes in the range of 0 ? 1.4 V with strong color changes and high contrast ratios in the visible and NIR regions upon electro‐oxidation. © 2016 The Authors. Journal of Polymer Science Part A: Polymer Chemistry Published by Wiley Periodicals, Inc. 2016, 54, 2476–2485  相似文献   

10.
The bis(phenylhydrazone) of substituted diphenacyl sulfides (=1,1′‐[thiobis(methylene)]bis[arylmethanone] bis(2‐phenylhydrazones)) 1 underwent a tandem sequence of reactions upon treatment with Vilsmeier reagent, ultimately yielding 3‐aroylindoles (=aryl(1H‐indol‐3‐yl)methanones) 3 (Scheme 1 and Table 1). The reaction seems to be product selective depending upon the reaction temperature.  相似文献   

11.
The structures of five compounds consisting of (prop‐2‐en‐1‐yl)bis[(pyridin‐2‐yl)methylidene]amine complexed with copper in both the CuI and CuII oxidation states are presented, namely chlorido{(prop‐2‐en‐1‐yl)bis[(pyridin‐2‐yl)methylidene]amine‐κ3N,N′,N′′}copper(I) 0.18‐hydrate, [CuCl(C15H17N3)]·0.18H2O, (1), catena‐poly[[copper(I)‐μ2‐(prop‐2‐en‐1‐yl)bis[(pyridin‐2‐yl)methylidene]amine‐κ5N,N′,N′′:C2,C3] perchlorate acetonitrile monosolvate], {[Cu(C15H17N3)]ClO4·CH3CN}n, (2), dichlorido{(prop‐2‐en‐1‐yl)bis[(pyridin‐2‐yl)methylidene]amine‐κ3N,N′,N′′}copper(II) dichloromethane monosolvate, [CuCl2(C15H17N3)]·CH2Cl2, (3), chlorido{(prop‐2‐en‐1‐yl)bis[(pyridin‐2‐yl)methylidene]amine‐κ3N,N′,N′′}copper(II) perchlorate, [CuCl(C15H17N3)]ClO4, (4), and di‐μ‐chlorido‐bis({(prop‐2‐en‐1‐yl)bis[(pyridin‐2‐yl)methylidene]amine‐κ3N,N′,N′′}copper(II)) bis(tetraphenylborate), [Cu2Cl2(C15H17N3)2][(C6H5)4B]2, (5). Systematic variation of the anion from a coordinating chloride to a noncoordinating perchlorate for two CuI complexes results in either a discrete molecular species, as in (1), or a one‐dimensional chain structure, as in (2). In complex (1), there are two crystallographically independent molecules in the asymmetric unit. Complex (2) consists of the CuI atom coordinated by the amine and pyridyl N atoms of one ligand and by the vinyl moiety of another unit related by the crystallographic screw axis, yielding a one‐dimensional chain parallel to the crystallographic b axis. Three complexes with CuII show that varying the anion composition from two chlorides, to a chloride and a perchlorate to a chloride and a tetraphenylborate results in discrete molecular species, as in (3) and (4), or a bridged bis‐μ‐chlorido complex, as in (5). Complex (3) shows two strongly bound Cl atoms, while complex (4) has one strongly bound Cl atom and a weaker coordination by one perchlorate O atom. The large noncoordinating tetraphenylborate anion in complex (5) results in the core‐bridged Cu2Cl2 moiety.  相似文献   

12.
The optical properties and electrical properties of a series of low‐band‐gap conjugated copolymers, in which alkyl side chains were substituted at various positions, were investigated using donor–acceptor conjugated copolymers consisting of a cyclopentadithiophene derivative and dithienyl‐benzothiadiazole. With substituted side chains, the intrinsic properties of the copolymers were significantly altered by perturbations of the intramolecular charge transfer. The absorption of poly[2, 6‐(4,4‐bis(2‐octyl)‐4H‐cyclopenta‐[2,1‐b:3,4‐b′]dithiophene)‐alt‐4, 7‐bis(4‐octyl‐thiophene‐2‐yl)benzo‐2,1,3‐thiadiazole] [ PCPDT‐ttOTBTOT ( P2 )], which assumed a tail–tail configuration, tended to blue shift relative to the absorption of poly[2,6‐(4,4‐bis(2‐octyl)‐4H‐cyclopenta‐[2,1‐b:3,4‐b′]dithiophene)‐alt‐4,7‐bis (thiophene‐2‐yl)benzo‐2,1,3‐thiadiazole] [ PCPDT‐TBTT ( P1 )]. The absorption of poly[2,6‐(4,4‐bis(2‐octyl)‐4H‐cyclopenta‐[2,1‐b:3, 4‐b′]dithiophene)‐alt‐4,7‐bis(3‐octyl‐thiophene‐2‐yl)benzo‐2,1,3‐thiadiazole] [ PCPDT‐hhOTBTOT ( P3 )], which assumed a head–head configuration, was blue shifted relative to that of P2 . The electrical transport properties of field‐effect transistors were sensitive to the side chain position. The field‐effect mobility in P2 (μ2 = 1.8 × 10?3 cm2/V s) was slightly lower than that in P1 (μ1 = 4.9 × 10?3 cm2/V s). However, the mobility of P3 was very low (μ3 = 3.8 × 10?6 cm2/V s). Photoexcitation spectroscopy showed that the charge generation efficiency (shown in transient absorption spectra) and polaron pair mobility in P1 and P2 were higher than in P3 , yielding P1 and P2 device performances that were better than the performance of devices based on P3 . © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011  相似文献   

13.
An efficient method for the synthesis of N‐alkylated 3‐(1‐benzyl‐1H‐1,2,3‐triazole‐4‐yl)‐9H‐carbazoles ( 5 , 6 , 7 , 8 , 9 , 10 ) and 9‐ethyl‐3,6‐di(1H‐1,2,3‐triazole‐4‐yl)‐9H‐carbazole ( 13 ) has been developed from nitroolefines. The effects of catalyst and solvent on these reactions have been investigated. p‐TsOH‐THF was found to be the best system for this reaction. Various triazolyl‐carbazoles were prepared in good to excellent yields.  相似文献   

14.
Two new ZnII coordination polymers, namely, catena‐poly[[dibromidozinc(II)]‐μ‐[3,6‐bis(pyridin‐4‐yl)phenanthrene‐9,10‐dione‐κ2N:N′]], [ZnBr2(C24H14N2O2)]n, (1), and poly[[bromido[μ3‐10‐hydroxy‐3,6‐bis(pyridin‐4‐yl)phenanthren‐9‐olato‐κ3N:N′:O9]zinc(II)] hemihydrate], {[ZnBr(C24H15N2O2)]·0.5H2O}n, (2), have been synthesized through hydrothermal reaction of ZnBr2 and a 60° angular phenanthrenedione‐based linker, i.e. 3,6‐bis(pyridin‐4‐yl)phenanthrene‐9,10‐dione, in different solvent systems. Single‐crystal analysis reveals that polymer (1) features one‐dimensional zigzag chains connected by weak C—H...π and π–π interactions to form a two‐dimensional network. The two‐dimensional networks are further stacked in an ABAB fashion along the a axis through C—H...O hydrogen bonds. Layers A and B comprise left‐ and right‐handed helical chains, respectively. Coordination polymer (2) displays a wave‐like two‐dimensional layered structure with helical chains. In this compound, there are two opposite helical –Zn–HL– chains [HL is 10‐hydroxy‐3,6‐bis(pyridin‐4‐yl)phenanthren‐9‐olate] in adjacent layers. The layers are packed in an ABAB sequence and are further connected through O—H...Br and O—H...O hydrogen‐bond interactions to form a three‐dimensional framework. In (1) and (2), the mutidentate L and HL ligands exhibits different coordination modes.  相似文献   

15.
As an important class of heterocyclic compounds, 1,3,4‐thiadiazoles have a broad range of potential applications in medicine, agriculture and materials chemistry, and were found to be excellent precursors for the crystal engineering of organometallic materials. The coordinating behaviour of allyl derivatives of 1,3,4‐thiadiazoles with respect to transition metal ions has been little studied. Five new crystalline copper(I) π‐complexes have been obtained by means of an alternating current electrochemical technique and have been characterized by single‐crystal X‐ray diffraction and IR spectroscopy. The compounds are bis[μ‐5‐methyl‐N‐(prop‐2‐en‐1‐yl)‐1,3,4‐thiadiazol‐2‐amine]bis[nitratocopper(I)], [Cu2(NO3)2(C6H9N3S)2], (1), bis[μ‐5‐methyl‐N‐(prop‐2‐en‐1‐yl)‐1,3,4‐thiadiazol‐2‐amine]bis[(tetrafluoroborato)copper(I)], [Cu2(BF4)2(C6H9N3S)2], (2), μ‐aqua‐bis{μ‐5‐[(prop‐2‐en‐1‐yl)sulfanyl]‐1,3,4‐thiadiazol‐2‐amine}bis[nitratocopper(I)], [Cu2(NO3)2(C5H7N3S2)2(H2O)], (3), μ‐aqua‐(hexafluorosilicato)bis{μ‐5‐[(prop‐2‐en‐1‐yl)sulfanyl]‐1,3,4‐thiadiazol‐2‐amine}dicopper(I)–acetonitrile–water (2/1/4), [Cu2(SiF6)(C5H7N3S2)2(H2O)]·0.5CH3CN·2H2O, (4), and μ‐benzenesulfonato‐bis{μ‐5‐[(prop‐2‐en‐1‐yl)sulfanyl]‐1,3,4‐thiadiazol‐2‐amine}dicopper(I) benzenesulfonate–methanol–water (1/1/1), [Cu2(C6H5O3S)(C5H7N3S2)2](C6H5O3S)·CH3OH·H2O, (5). The structure of the ligand 5‐methyl‐N‐(prop‐2‐en‐1‐yl)‐1,3,4‐thiadiazol‐2‐amine (Mepeta ), C6H9N3S, was also structurally characterized. Both Mepeta and 5‐[(prop‐2‐en‐1‐yl)sulfanyl]‐1,3,4‐thiadiazol‐2‐amine (Pesta ) (denoted L ) reveal a strong tendency to form dimeric {Cu2L 2}2+ fragments, being attached to the metal atom in a chelating–bridging mode via two thiadiazole N atoms and an allylic C=C bond. Flexibility of the {Cu2(Pesta )2}2+ unit allows the CuI atom site to be split into two positions with different metal‐coordination environments, thus enabling the competitive participation of different molecules in bonding to the metal centre. The Pesta ligand in (4) allows the CuI atom to vary between water O‐atom and hexafluorosilicate F‐atom coordination, resulting in the rare case of a direct CuI…FSiF52− interaction. Extensive three‐dimensional hydrogen‐bonding patterns are formed in the reported crystal structures. Complex (5) should be considered as the first known example of a CuI(C6H5SO3) coordination compound. To determine the hydrogen‐bond interactions in the structures of (1) and (2), a Hirshfeld surface analysis has been performed.  相似文献   

16.
Two new NiII complexes involving the ancillary ligand bis[(pyridin‐2‐yl)methyl]amine (bpma) and two different carboxylate ligands, i.e. homophthalate [hph; systematic name: 2‐(2‐carboxylatophenyl)acetate] and benzene‐1,2,4,5‐tetracarboxylate (btc), namely catena‐poly[[aqua{bis[(pyridin‐2‐yl)methyl]amine‐κ3N,N′,N′′}nickel(II)]‐μ‐2‐(2‐carboxylatophenyl)aceteto‐κ2O:O′], [Ni(C9H6O4)(C12H13N3)(H2O)]n, and (μ‐benzene‐1,2,4,5‐tetracarboxylato‐κ4O1,O2:O4,O5)bis(aqua{bis[(pyridin‐2‐yl)methyl]amine‐κ3N,N′,N′′}nickel(II)) bis(triaqua{bis[(pyridin‐2‐yl)methyl]amine‐κ3N,N′,N′′}nickel(II)) benzene‐1,2,4,5‐tetracarboxylate hexahydrate, [Ni2(C10H2O8)(C12H13N3)2(H2O)2]·[Ni(C12H13N3)(H2O)3]2(C10H2O8)·6H2O, (II), are presented. Compound (I) is a one‐dimensional polymer with hph acting as a bridging ligand and with the chains linked by weak C—H...O interactions. The structure of compound (II) is much more complex, with two independent NiII centres having different environments, one of them as part of centrosymmetric [Ni(bpma)(H2O)]2(btc) dinuclear complexes and the other in mononuclear [Ni(bpma)(H2O)3]2+ cations which (in a 2:1 ratio) provide charge balance for btc4− anions. A profuse hydrogen‐bonding scheme, where both coordinated and crystal water molecules play a crucial role, provides the supramolecular linkage of the different groups.  相似文献   

17.
Two benzotriazole derivative dyes 4,7‐bis(2,3‐dihydrothieno[3,4‐b][1,4]dioxin‐5‐yl)‐2‐dodecyl‐2H‐benzo[1,2,3]triazole, and 2‐dodecyl‐4,7‐bis(4‐hexylthiophen‐2‐yl)‐2H‐benzo[d][1,2,3]triazole are shown to work as efficient photosensitizers for a diphenyliodonium salt initiator in cationic photopolymerization of epoxide and vinyl monomers. Substituted thienyl groups are attached to benzotriazole backbone to extend conjugation and enhance electron density of the molecules. Thereby, it was possible to initiate polymerizations at room temperature using long wavelength UV and visible light. The progress of photopolymerizations was monitored using optical pyrometry. The photopolymerization of an epoxide monomer using solar irradiation was also demonstrated. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011  相似文献   

18.
In this study, two new dibenzofuran derivatives featuring one or two cyanocarbazole units, 6‐(dibenzo[b,d]furan‐4‐yl)‐9‐phenyl‐9H‐carbazole‐3‐carbonitrile ( mBFCzCN) and 6,6′‐(dibenzo[b,d]furan‐4,6‐diyl)bis(9‐phenyl‐9H‐carbazole‐3‐carbonitrile) ( dBFCzCN ), were developed as host materials for phosphorescent organic light emitting diodes (PhOLEDs). A new molecular design connecting the cyanocarbazole to the dibenzofuran using the cyanocarbazole 6‐position instead of its 9‐position was created, and the effects of number of cyanocarbazole units in the dibenzofuran building block on the photophysical and electroluminescence properties were investigated in detail. The mBFCzCN compound revealed high triplet energy (2.78 eV) than that of dBFCzCN (2.68 eV) and good bipolar charge transporting properties. The potential of these materials as hosts for blue and green PhOLEDs was investigated using bis(4,6‐(difluorophenyl)pyridinato‐N,C2′)picolinate iridium(III) (FIrpic) and tris(2‐phenylpyridinato)iridium(III) (Ir(ppy)3) dopants, respectively. The results indicated that the mBFCzCN with one cyanocarbazole unit showed better device performance than the dBFCzCN with two cyanocarbazole units in the blue and green devices. High external quantum efficiencies of 19.0 and 21.2 % were demonstrated in the blue and green PhOLEDs with the mBFCzCN host due to its high triplet energy and good bipolar charge transporting characteristics.  相似文献   

19.
A new nano‐sized rigid double‐armed oxadiazole‐bridged organic ligand, 2,5‐bis{2‐methyl‐5‐[2‐(pyridin‐3‐yl)ethenyl]phenyl}‐1,3,4‐oxadiazole, C30H20N4O, L or (I), which adopts a cis conformation in the solid state, has been synthesized and used to create the two novel metallocycle complexes (2,5‐bis{2‐methyl‐5‐[2‐(pyridin‐3‐yl‐κN)ethenyl]phenyl}‐1,3,4‐oxadiazole)diiodidocadmium(II) dichloromethane monosolvate, [CdI2(C30H20N4O)]·CH2Cl2, (II), and di‐μ‐iodido‐bis[(2,5‐bis{2‐methyl‐5‐[2‐(pyridin‐3‐yl‐κN)ethenyl]phenyl}‐1,3,4‐oxadiazole)copper(I)], [Cu2I2(C30H20N4O)2], (III). Molecules of complex (II) adopts a 20‐membered `0'‐shaped metallocycle structure with crystallographic mirror symmetry. The discrete units are linked into one‐dimensional chains through intermolecular π–π and C—H...π interactions. In (III), the two I atoms and two CuI atoms form a {Cu2(μ‐I)2} cluster. One {Cu2(μ‐I)2} cluster and two L ligands form two 20‐membered monometallic rings in a head‐to‐head fashion, leading to a discrete centrosymmetric `8'‐shaped metallocyclic complex. These metallocycles stack together via two kinds of intermolecular π–π interactions to generate a two‐dimensional network in the ac plane. The luminescence properties of (I)–(III) were investigated in the solid state at room temperature and displayed an obvious red shift.  相似文献   

20.
New methacrylate monomers with carbazole moieties as pendant groups were synthesized by multistep syntheses starting from carbazoles with biphenyl substituents in the aromatic ring. The corresponding polymers were prepared using a free‐radical polymerization. The novel polymers contain N‐alkylated carbazoles mono‐ or bi‐substituted with biphenyl groups in the aromatic ring. N‐alkyl chains in polymers vary by length and structure. All new polymers were synthesized to evaluate the structural changes in terms of their effect on the energy profile, thermal, dielectric, and photophysical properties when compared to the parent polymer poly(2‐(9H‐carbazol‐9‐yl)ethyl methacrylate). According to the obtained results, these compounds may be well suited for memory resistor devices. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 70–76  相似文献   

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