JOURNAL OF PORPHYRINS AND PHTHALOCYANINES
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2018
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IF 1.217
Xiangfei Kong,Hongkang Gong,Shengping Dai,Wei Yao,Linping Mu,Shufen Zhang,Guixia Wang
Five novel dyads, consisting of a tetraphenylporphyrine unit connected to a perylene monoimide diester unit via a flexible bridge -CONH-(CH 2 ) n - (n = 4, 6, 8, 10 and 12), have been synthesized. Their structures were characterized by 13 C and 1 H nuclear magnetic resonance spectroscopy, infrared spectroscopy, mass spectrometry and elemental analysis. The UV-vis absorption spectra revealed these dyads have broad optical absorption in the ultraviolet and visible regions due to the complementary absorption of the two units. The differential scanning calorimetry traces and polarized optical microscopy textures showed all these dyads have columnar liquid crystal phases. Cyclic voltammetry revealed the highest occupied molecular orbitals of the dyads located on the porphyrin units, and the lowest unoccupied molecular orbitals located on the perylene units. In addition, these results were in agreement with that of the theoretical modeling. When excited at 423 or 473 nm, the photoluminescent emission spectra showed that the degree of fluorescence quenching of porphyrin units increased as the spacers became shorter. This quenching was ascribed to intramolecular photoinduced electron transfer, which also induced the dyad molecules to form the charge-separated states. The charge-separated molecules were further confirmed by the photocurrent response curves. These behaviors of broad absorption of the ultraviolet-visible light, yielding the charge-separated states of the molecules when excited and the formation of columnar liquid crystal phase made these dyads candidates for single-component photovoltaic active materials.
研究领域:
材料科学
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化学
·
光子学
✓ 已验证
DOI
高影响因子
LIQUID CRYSTALS
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2012
·
IF 1.858
Fafu Yang,Jianwei Xie,Hongyu Guo,Bingting Xu,Congcong Li
Series of novel 1,3,5-triazine-based triphenylene oligomers 7, 10 and 12 with large bridging polyaromatic core were designed and synthesised by simple procedures in high yields. Their structures were confirmed by FTIR, 1H NMR, ESI-MS and elemental analyses. Their mesomorphic behaviours were studied by differential scanning calorimetry, polarising optical microscopy and X-ray diffraction. 1,3,5-triazine-based triphenylene monomer 7 has no mesomorphic property, but 1,3,5-triazine-based triphenylene dimer 10 and 1,3,5-triazine-based triphenylene trimer 12 possess excellent mesomorphic properties. The mesomorphic temperature range of compound 12 was as wide as 180°C. These studies indicated that the mesomorphic properties were determined by the numbers of triphenylene units. More units of triphenylene in the oligomers resulted in better mesomorphic properties.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
LIQUID CRYSTALS
·
2019
·
IF 3.078
Duo Wang,Yuan-Yuan Quan,Qing-Qing He,Ji-Wen Hu,Mei Tian,Ying-Gang Jia,Dan-Shu Yao
Two series of novel four-arm azobenzene liquid crystal molecules were designed and synthesized, and their mesophase properties, photo-induced transition were studied. Two series of mesogenic arms were screened with different length of flexible chain (the carbon number n of flexible chain is 4, 6, 8, 10) using methoxy and nitro as terminal substituents R. The four-arm azobenzene LCs were synthesized by introducing the mesogenic arms into cholic acid. FACAE-O-n, FACAE-N-n all belonged to photosensitive thermotropic enantiotropicnematic LCs. For methoxyl series, melting transitions (Tm), liquid crystal-isotropic transitions (Ti) and mesogenic ranges decreased with the increase of carbon numbers in flexible chain both on heating and cooling. The mesophase performance of FACAE-O-4 was the most excellent. For nitro series, Tm and Ti on heating and cooling decreased with the increase of carbon numbers. Nevertheless, mesogenic ranges increased with the increase of carbon numbers only on heating. The cooling mesogenic ranges showed a trend of rising firstly and then falling, reaching the maximum 103.1oC (n=8). Under ultraviolet irradiation, there was no red shift. The intensity of maximum absorption has changed with the increase of ultraviolet irradiation time. After photo-induced, Tm and Ti on heating and cooling of the four-arm LCs decreased, and the mesogenic ranges became shorter.
研究领域:
材料化学
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液晶研究
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有机合成
✓ 已验证
DOI
高影响因子
LIQUID CRYSTALS
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2014
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IF 2.349
Fafu Yang,Jin Yuan,Congcong Li,Hongyu Guo,Xiaoyun Yan
Series of triphenylene derivatives with multiple NH groups 3a, 3b, 4a, 4b, 5a and 5b were designed and synthesised by simple procedures in high yields. Their structures were confirmed by Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), mass spectrometry (MS) and elemental analysis. Their mesophase behaviours were studied by differential scanning calorimetry, polarising optical microscopy and X-ray diffraction. The triphenylene derivatives 3a and 3b with two NH groups and triphenylene derivatives 4a and 4b with three NH groups possess excellent mesomorphic properties. Compounds 4a and 4b exhibited wider mesophase than compounds 3a and 3b. Triphenylene derivatives 5a and 5b with five NH groups have no mesomorphic properties. These results suggested the units of hydrogen bonds played the crucial roles on mesomorphic properties and acylthiosemicarbazide group with three NH groups was a good functional group for producing excellent mesomorphic properties.
研究领域:
材料化学
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物理化学
✓ 已验证
DOI
高影响因子
LIQUID CRYSTALS
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2020
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IF 2.908
Duo Wang,Ruo-Yan Li,Yuan-Yuan Quan,Qing-Qing He,Mei Tian,Dan-Shu Yao
Twenty novel azobenzene liquid crystal micromolecular compounds named ω-[4-(p-substituted azobenzeneoxy carbonyl]acid (X-ABCnA) have been designed and synthesised, followed by studies on the thermal performance and mesomorphic properties of the compounds. The liquid crystal compounds were divided into five homologous series based on the terminal substituents R (R = CH3O, CH3, H, Cl, NO2). In each series, the number of carbons on flexible chain was 4, 6, 8 and 10, respectively. Fourier-transform infrared, proton nuclear magnetic resonance and elementary analysis demonstrated that the structure of the synthesised azobenzene liquid crystal compounds was consistent with the molecular design. The mesomorphic properties were tested, analysed and characterised by using differential scanning calorimetry and polarised optical microscopy. The melting transition (Tm) of all the compounds in homologous series with different substituents appeared to decrease with the increase of carbon numbers on flexible chains. The same held true for the temperature of isotropic-mesophase/crystalline transition. The compounds with stronger polarity of terminal substituents were more likely to form broader mesogenic ranges. The liquid crystal compounds discussed in this work can be regarded as a reference for the synthesis of mesogenic arms participating in the synthesis of novel multi-arm liquid crystalline macromolecules and polymers.
研究领域:
材料科学
·
有机化学
✓ 已验证
产品关联
DOI
高影响因子
LIQUID CRYSTALS
·
2019
·
IF 3.078
Shengbo Zhu,Yangyang Zhu,Jin Chigan,Yuqiao Fu,Qiang Weng,Xiaoling Niu,Weixing Chen,Ran Chen,Xinbing Chen,Zhongwei An
A series of biphenyl ester compounds with alkenyl, alkyl, oxirane, and 1,3-dioxolane as the terminal groups have been synthesised for investigating the mesomorphic and thermal stability. Based on the same carbon skeleton, the allyl-terminated compound V1OLC has no mesophase, while the oxirane-terminated compound POLC not only has wider multiple smectic mesophase compared with the propyl-terminated compound 3OLC but also exhibits the best thermal stability. However, when the terminal groups change from oxirane to 1,3-dioxolane, EOLC shows neither mesophase nor the good thermal stability. In addition, with the extension of the terminal chains, the butyl-terminated compound 4OLC gives the widest smectic mesophase. These imply that the mesomorphic and thermal stability of these biphenyl ester compounds are dependent on the suitable terminal chain lengths and epoxy sizes. Meanwhile, Density Functional Theory (DFT) calculations were conducted to assist in analysing the experimental results.
研究领域:
材料科学
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物理化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
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2023
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IF 6
Wenjie Bi,Zhiyuan Zheng,Yue Wang,Ziyang Shi,Kunlun Wang,Yingliang Liu,Shengang Xu,Shaokui Cao
Discotic liquid crystalline polymers (DLCPs) combining the advantages of discotic liquid crystals and polymers yet have been less developed compared to the calamitic counterparts mainly due to lack of DLCP materials. Here, mesogen-jacketed liquid crystalline polymers with pendant fluorinated triphenylene were successfully synthesized via proper polymerizations of the corresponding monomers respectively. Nuclear magnetic resonance spectroscopy (both 1 H NMR and 13 C NMR), time-of-flight mass spectrometry (MALDI-TOF MS), Fourier transform Infrared (FT-IR) spectroscopy and other characterization methods were used to confirm the structure of the products. The mesomorphic properties of the obtained triphenylene monomers with unsaturated flexible tails and resulting polymers were investigated by polarizing optical microscopy (POM), differential scanning calorimetry (DSC), and X-ray diffractometer (XRD). The propargylene-containing monomer shows a smectic liquid crystals phase and the pentynylene monomer exhibit a highly ordered columnar helical liquid crystal phase. The three side chain polymers containing fluorinated triphenylene have good thermal stability (decomposition temperature of 350 °C or above). At the same time, the polymers prepared by the polymerization of propargylene-containing monomers have both hexagonal columnar phase (Col h ) and rectangular columnar phases (Col r ). The polymers with long spacer chains derived from Methyl acrylate have a hexagonal columnar structure (Col h ). The fluorinated triphenylene monomers and polymers with ordered liquid crystal phases synthesized in this work provide useful inspiring for structural modifications of DLCPs and are promising for applications in organic optoelectronics.
研究领域:
材料科学
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高分子化学
✓ 已验证
产品关联
DOI
高影响因子
LIQUID CRYSTALS
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2010
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IF 1.451
Yan Li,Xinbing Chen,Pei Chen,Zhongwei An,Juan Li
A new series of fused polyheterocyclic aromatic compounds, 7-alkoxybezopyrano[2,3-c]pyrazol-3-one (C-
n
BPP), were synthesised and characterised by infrared, 1H-nuclear magnetic resonance (NMR), 13C-NMR and two-dimensional 1H-13C cosy spectra. Their phase transition behaviour was investigated by differential scanning calorimetry and polarising optical microscopy. All of these compounds showed enantiotropic mesophases with temperature domains of 12–60°C and 22–69°C on heating and cooling processes for a carbon number of the alkoxy chain from 2 to 10. The effect of the length of the alkoxy chain on the mesomorphic properties was discussed. Comparison of C-
n
BPP and several kinds of coumarin derivatives indicated that the intermolecular hydrogen bonding acted as the driving force of the mesophase formation.
研究领域:
有机化学
·
材料科学
✓ 已验证
DOI
高影响因子
SOFT MATERIALS
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2013
·
IF 1.429
Fafu Yang,Lihong Zhang,Bingting Xu,Xiaoyuan Su,Hongyu Guo
The syntheses of novel triphenylene-ferrocene dyads linked by long or short chain containing conjugated structures were reported in good yields. Their electrochemical properties and mesophase behaviors were investigated by cyclic voltammetry, differential scanning calorimetry, polarizing optical microscopy, and X-ray diffraction, respectively. Triphenylene-ferrocene dyad with long chain containing conjugated structure 5 possessed redox property but no mesomorphic property. Triphenylene-ferrocene dyad with short chain containing conjugated structure 7 exhibited not only reversible electrochemical response property but also ordered hexagonal columnar mesophase for the first time.
[Supplementary materials are available for this article. Go to the publisher's online edition of Soft Materials for the following free supplemental resource(s): First Triphenylene-Ferrocene Dyad with Redox Behavior and Mesomorphic Property]
研究领域:
材料科学
·
电化学
·
分子设计与合成
✓ 已验证
DOI
高影响因子
LIQUID CRYSTALS
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2013
·
IF 1.959
Lina Zhang,Xinbing Chen,Fengqi Zhao,Xuezhong Fan,Pei Chen,Zhongwei An
Three series of 2-(4′-alkoxybiphenyl-4-yl)-1H-benzimidazole derivatives (nM-x), which possessed 5-nitrobenzimidazole (nM-N series), benzimidazole (nM-H series) or 5-methylbenzimidazole (nM-M series) units at the end of the molecule, were synthesised and characterised by infrared, 1H- and 13C-nuclear magnetic resonance spectra, electrospray ionisation-mass spectrometry and elemental analysis. Their phase transition behaviour was investigated by differential scanning calorimetry, polarising optical microscopy and X-ray diffraction. All the compounds exhibited enantiotropic smectic mesophases with wide temperature domains for a carbon number in the alkoxy chain from 6 to 16, where the mesophase ranges were 14–91°C and 17–99°C during heating and cooling processes for the nM-N compounds, 7–25°C and 8–49°C for the nM-H compounds and 48–81°C and 52–85°C for the nM-M compounds, respectively. The effect of the length of alkoxy chain on mesomorphic properties was discussed. The nM-N and nM-M exhibited a much wider mesophase range whether during heating or cooling process than the corresponding nM-H series, especially for the longer terminal chain (n > 8), which indicated that the substituent in the benzimidazole moiety was helpful in increasing the mesophase stability.
研究领域:
有机化学
·
材料科学
✓ 已验证
DOI
高影响因子
DYES AND PIGMENTS
·
2018
·
IF 3.767
Shengjie Jiang,Jiabin Qiu,Yunxiang Chen,Hongyu Guo,Fafu Yang
A series of novel tetraphenylethylene aromatic acylhydrazone derivatives 11 , 12 and 13 with 4, 8 or 12 alkyl chains were designed and synthesized in yields of 82–85%. Studies on the mesomorphic properties suggested the ordered hexagonal columnar mesophase for compounds 11 , 12 and 13 . The increase in the number of alkyl chains was favourable for decreasing the phase-transition temperatures and extending the mesophase temperature range. Further, samples 11 , 12 and 13 presented an excellent AIE effect. The fluorescence intensities increased by 70, 84 and 43 times for samples 11 , 12 and 13 , respectively. The absolute fluorescence quantum yields were 18.7%, 27.4% and 23.8% in solid films at room temperature and 6.7%, 24.2% and 17.3% in the mesophase. These results suggested that the number of alkyl chains greatly influenced the fluorescence emission and sample 12 with 8 alkyl chains exhibited the strongest fluorescence emission. Sample 12 also displayed the electroluminescence performance on OLED device.
研究领域:
材料科学
·
化学
·
光电
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）