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1.
赵可清  高彩艳  胡平  汪必琴  李权 《化学学报》2006,64(10):1051-1062
合成了三个系列, 共二十四个有两种不同软链的对称和非对称苯并菲盘状液晶化合物, C18H6(OR)3- (OCH2COOEt)3, C18H6(OR)3(OCH2COOBu)3, C18H6(OR)3(OCH2CONHBu)3, 其中R=C5H11, C6H13, C7H15, C8H17. 化合物通过柱层析纯化, 结构通过1H NMR, IR, 元素分析等确证. 化合物热稳定性通过TGA测定, 并显示出较高的热稳定性. 通过偏光显微镜和差视扫描量热法对这些化合物的热致液晶性进行了研究. 结果显示: 对于苯并菲液晶化合物C18H6(OR)3(OCH2COOEt)3, 非对称性化合物较之对称异构体化合物有更低的熔点和更高的清亮点, 因而非对称性化合物有更宽的介晶温度范围. 对于分子中含有酰胺基的苯并菲液晶化合物C18H6(OR)3(OCH2CONHBu)3, 对称化合物有比非对称异构体更高的清亮点和更有序的六方柱状介晶相, 且其与具有同样软链长度的分子中不含酰胺基的化合物系列C18H6(OR)3(OCH2COOBu)3相比较, 由于柱内分子间氢键的形成, 不仅有更高的熔点和清亮点, 而且有更丰富的柱状介晶相.  相似文献   

2.
余文浩  赵可清  汪必琴  胡平 《化学学报》2007,65(12):1140-1148
盘状液晶分子能自组装成高度有序的六方柱状介晶相. 其各向异性的载流子高速迁移率使其成为较理想的有机光电子材料. 采用分子间氢键锚定柱状相, 获得介晶相温度范围宽、有序度高的苯并菲盘状液晶是本研究的目的. 本文通过分子设计, 合成了3个系列, 共18个有两种不同软链的苯并菲盘状液晶化合物C18H6(OR)5(OCH2COOEt), C18H6(OR)5(OCH2COOBu)和C18H6(OR)5(OCH2CONHBu), 其中R=CnH2n+1, n=4~9. 化合物的纯度和结构通过1H NMR和元素分析确证. 化合物热稳定性通过热重分析(TGA)测定, 并显示出较高的热稳定性. 通过偏光显微镜(POM)和差示扫描量热法(DSC)对这些化合物的热致液晶性进行了研究. 结果显示对于分子中含有酰胺基的苯并菲液晶化合物C18H6(OR)5(OCH2CONHBu), 与具有同样软链长度的分子中不含酰胺键的化合物系列C18H6(OR)5(OCH2COOBu)相比较, 前者由于柱内分子间氢键的形成, 具有更高的熔点和清亮点.  相似文献   

3.
有玻璃态和液晶态的胆甾烯基苯并菲的合成及介晶性   总被引:1,自引:0,他引:1  
宋质琼  赵可清  胡平  汪必琴 《化学学报》2008,66(11):1344-1352
将盘状液晶基元苯并菲与手性向列型液晶基元胆甾烯基结合的化合物, 可望出现全新的性质. 合成了含有胆甾烯基的苯并菲化合物C18H6(OC5H11)5(OC5H10COOCh) (2), 2,7-C18H6(OC5H11)4(OC5H10COOCh)2 (4), C18H6(OR)3(OCnH2nCOO- Ch)3 (R=C5H11, C7H15, C9H19, C11H23, n=1, 5, 10) (6a~6f), C18H6(OC5H10COOCh)6 (Ch: cholesteryl) (8). 偏光显微镜和差示扫描量热法对这些化合物的热致介晶性研究结果显示, 化合物 4, 6a~6e具有手性盘状向列相和玻璃态, 8呈现近晶B相(SB)和玻璃态. 随间隔基长度n和烷基链R碳原子数的增加, 化合物玻璃化温度和清亮点呈下降趋势. 随着胆甾烯基数目减少, 化合物的玻璃化温度和清亮点降低.  相似文献   

4.
陈红梅  赵可清  胡平  汪必琴 《化学学报》2007,65(14):1368-1376
全氟烃链的憎氟效应(fluorophobic effect)可有效地促使棒状分子形成近晶相, 并稳定液晶相. 为进一步探讨氟效应对盘状分子介晶性的影响, 合成了一系列全氟酯链的苯并菲化合物C18H6(OCnH2n+1)5(OCOC2H4C6F13) (a), 以及另一系列相对应的不含氟化合物C18H6(OCnH2n+1)5(OCOC8H17) (b), n=4~9. DSC检测和偏光显微镜观察显示两类化合物都为柱状相热致型液晶. 化合物a与相对应的化合物b比较, 其熔点和清亮点上升, 柱状相的热稳定性增强.  相似文献   

5.
《高等学校化学学报》1999,20(8):1172-1178
利用Co2(CO)8与[Cl3CC(O)OCH2]2的反应合成了以C(O)OCH2CH2OC(O)桥联两个Co3C四面体骨架为特征的新型双四面体簇合物[(CO)9Co33-C)C(O)OCH2]2(1);1与不同物质的量比的Na[M(CO)3C5H4R](M=Mo,W;R=H,C(O)Me)反应,得到一步交换的产物(CO)9Co33-C)C(O)OCH2CH2OC(O)(μ3-C)Co2M(CO)8(C5H4R)[M=Mo,R=H(2);M=Mo,R=C(O)Me(3);M=W,R=H(4);M=W,R=C(O)Me(5)]或两步交换的产物[(C5H4R)(CO)8Co2M(μ3-C)C(O)OCH2]2[M=Mo,R=H(6);M=Mo,R=C(O)Me(7);M=W,R=H(8);M=W,R=C(O)Me(9)].5或9分别与Na[Mo(CO)3C5H5]以12的物质的量比反应得到含一个手性四面体骨架(CoMoWC)的(C5H5)(CO)8Co2Mo(μ3-C)C(O)OCH2CH2O·C(O)(μ3-C)CoMoW(CO)7(C5H4C(O)Me)(C5H5)(10)或含两个手性四面体骨架(CoMoWC)的[(C5H5)(C5H4C(O)Me)(CO)7CoMoW(μ3-C)C(O)OCH2]2(11);对化合物1_11进行了CH元素分析、IR和1HNMR等表征.结果表明,在金属交换反应中处于不同簇环境下的Co(CO)3基团反应活性不同.对化合物1进行了晶体X射线衍射分析.化合物1的晶体属单斜晶系,P21/n(#14)空间群,晶胞参数a=0.933 0(2)nm,b=1.519 7(4)nm,c=1.178 3(4)nm,=91.16(2)°,Z=2,F(000)=972.分子结构呈中心对称.  相似文献   

6.
朱任宏  方聖鼎 《化学学报》1965,31(3):222-228
从云南省昭通县产的雪上一枝蒿中共分得生物碱五种,其中三种为已知物,即烏头碱、次岛头碱和一枝蒿乙素,另二种为新生物碱,暂名为一枝蒿戊素和己素。一枝蒿戊素的分子式为C24H39O6N,其示性式为C19H22(OH)3(OCH3)3-(N·C2H5);一枝蒿己素的分子式为C24H39O7N,其示性式为C19H21(OH)4(OCH3)3(N·C2H5);另从云南省东川县出产的雪上一枝蒿中,尚分得一新生物碱,暂称为一枝蒿庚素,分子式为C21H31O3N,其示性式为C19H24(:O)(OH)2(N·C2H5)。  相似文献   

7.
为使不对称Ru-Fe化合物能在表面上自组装形成单分子膜,对trans-RuCl(dppm)2(C≡CFc)[Fc=C5H4FeC5H5,dppm=(C6H5)2PCH2P(C6H5)2](1)进行修饰,得到Ru(dppm)2(C≡CFc)(C≡CPhOCH3)(2),[Ru(dppm)2(C≡CFc)(N≡CCH2CH2NH2)][PF6](3)和[Ru(dppm)2(C≡CFc)(N≡CCH2CH2NHC(O)·(CH2)10SH)][PF6](4),并详细研究了该系列化合物的电化学性质.循环伏安结果显示出Ru周围配体得失电子能力的差别,直接影响了Ru中心的氧化-还原性,但这种影响并没有通过共轭的炔键传递到二茂铁中的Fe中心.化合物4可以在Au表面上自组装形成稳定、有序的单分子膜.还利用循环伏安法研究了单分子膜的形成过程及其表面覆盖率.  相似文献   

8.
以磷钼酸、 2-氨基吡啶、 五氧化二钒、 氯化锌和氯化镍等为主要原料, 采用水热方法合成了2个簇基超分子化合物[H3PMo12O40]2[C5H6N2]6(1)和[H2PMo12V2O42][C5H6N2]5·3H2O(2)(C5H6N2=2-氨基吡啶). 通过元素分析、 红外光谱、 紫外-可见光谱、 X射线光电子能谱、 热重分析、 X射线单晶衍射及X射线粉末衍射等手段对化合物进行了结构表征. 结构分析显示, 簇单元不同的2个超分子化合物以各自独特的堆积方式形成三维超分子网络. 利用苯乙烯的环氧化反应研究了2个化合物的催化性能.  相似文献   

9.
含全氟烃基的联苯酯类液晶的合成及其介晶性   总被引:2,自引:0,他引:2  
汪必琴  王新玲  赵可清  胡平 《化学学报》2007,65(21):2499-2504
全氟烃或半氟烃链无手性液晶化合物可能呈现铁电液晶性, 具有较大的学术及应用价值而受到研究人员的重视. 合成了全氟己基苯甲酸联苯酯类液晶化合物: ROC6H4C6H4O2CC6H4C6F13 (3a~3e), C3H7C6H4C6H4O2CC6H4C6F13 (6a)及其烃衍生物. 用差示扫描量热法(DSC)和偏光显微镜(POM)对其介晶性研究发现: 烃衍生物呈有序度较低的向列相, 熔点较高, 清亮点较低, 液晶相较窄. 全氟烃基取代的化合物出现多个有序度较高的近晶相, 熔点较低, 清亮点高, 介晶相温度范围宽.  相似文献   

10.
采用密度泛函理论(DFT)计算了MgAl-LDHs层板与无机阴离子(F-、Cl-、NO3-、CO32-、SO42-)和有机阴离子(水杨酸根离子([HO(C6H4)COO]-)、苯甲酸根离子([(C6H5)COO]-)、对二甲氨基苯甲酸根离子([p-(CH3)2N(C6H4)COO]-)、十二烷基磺酸根离子[C12H25SO3]-、己烷基磺酸根离子[C6H13SO3]-、丙烷基磺酸根离子[C3H7SO3]-)间的相互作用,获得稳定超分子几何结构及相互作用能。层板主体与客体间存在较强的超分子作用,包括主客体间静电作用和氢键等。主、客体间相互作用能数值大小顺序为CO32- > SO42- > F-> Cl-> NO3-;[p-(CH3)2N(C6H4)COO]-> [(C6H5)COO]-> [HO(C6H4)COO]-和[C12H25SO3]-> [C6H13SO3]- > [C3H7SO3]-。另外,还采用自然键轨道(NBO)计算和分析了LDHs 层板与阴离子间作用机理,从二阶微扰理论计算得到的稳定化能变化趋势与相互作用能数据基本吻合。  相似文献   

11.
Small change in chemical structure of discotic liquid crystals can cause big difference in their mesomorphism. Replacing of the alkoxy peripheral chains of triphenylene by oxygen-atom containing ester chains would result in novel mesomorphism. A series of mixed tail triphenylenes containing propoxyacetyloxy and alkoxy, abbreviated as C18H6(OCnH2n+1)3(OCOCH2OC3H7)3, n=4-8, and hexa(propyloxyacetyloxy)triphenylene, C18H6(OCOCH2OC3H7)6 were synthesized. Thermal gravimetry analysis (TGA) of three discogens showed that they had good thermal stability till 350 ℃. The mesomorphism was investigated through differential scanning calorimetry (DSC) and polarized optical microscopy (POM). The preliminary X-ray diffraction (XRD) results of one compound showed that it exhibited ordered hexagonal columnar (Colho) mesophase. These mixed tail triphenylene derivatives possessed much stable Colho mesophase and wider mesophase ranges than their hexaalkoxytriphenylene C18H6(OR)6 and hexaalkanoyloxytriphenylene C18H6(OCOR')6 analogues. The asymmetrical compounds 2,6,11-trialkoxy-3,7,10-tri(2-propyloxyacetyloxy)triphenylenes with n=5-8 displayed higher clearing points and wider temperature ranges than their symmetrical isomers 2,6,10-trialkoxy-3,7,11-tri(2-propyloxyacetyloxy)- triphenylenes, while C18H6(OCOCH2OC3H7)6 had the highest clearing point due to the β-oxygen-atom effect.  相似文献   

12.
New symmetrical and asymmetrical triphenylene-containing discotic liquid crystals with two different peripheral alkyl chains, known as sym-TP(OC6H13)3(OR)3 and asym-TP(OC6H13)3(OR)3, were synthesized. Their thermotropic liquid crystal properties were investigated through polarizing optical microscopy (POM), differential scanning calorimetry (DSC) and X-ray diffraction (XRD) analyses. The asyrranetdcal discogens are 2,6,11-rialkoxy-3,7,10-trihexyloxytriphenylenes, with the alkyl chain carbon numbers varying from 3-10, 12, and 14, while the symmetrical compounds are 2,6,10-trialkyloxy-3,7,11-trihexyloxytriphenylene. Two fluoroalkoxy substituted triphenylene discogens, 2,6,10-td(4,4,4-trifluorobutoxy)-3,7,11-trihexyloxytriphenylene and its asymmetrical isomer 2,6,11-tri(4,4,4-trifluorobutoxy)-3,7,10-trihexyloxytdphenylene were prepared. These two compounds show higher melting and clearing points than their alkoxy analogs, which implies that fluorophilic effect exists in the formation and stabilization of discotic columnar mesophase. The triphenylene derivatives TP(OC6H13)3(OR)3 with two different peripheral chains, symmetrically or asymmetrically attached on triphenylene cores, have lower melting points and clearing points than those of the higher symmetrical compounds TP(OR)6 with the same total chain carbon numbers. The mixed-chain-triphenylenes with longer alkoxy chains (n=9,10,12,14) show columnarmesophase at room temperature.  相似文献   

13.
Symmetrical and asymmetrical triphenylene discotic liquid crystals with two kinds of different peripheral chains, sym-TP(OC11H23)3(O2CR)3 and asym-TP(OC11H23)3(O2CR)3, (R=CH2OC2H5, CH2OC3H7, CH2OC4H9, CH2OC5H11, C3H7, C4H9, C5H11, C6H13, C7H15) were synthesized. Their thermotropic liquid crystalline properties were studied by polarizing optical microscopy (POM) and differential scanning calorimetry (DSC). The results showed that the asymmetrical compounds had higher melting and clearing points than that of their corresponding symmetrical compounds. For the same series of compounds, TP(OC11H23)3(O2CR)3, their melting points decrease and clearing points increase gradually with the lengthening of ester chains. Most of the β-oxygen containing esters of triphenylene derivatives, TP (OC11H23)3(O2CR)3, (R=CH2OC2H5, CH2OC3H7, CH2OC4H9, CH2OC5H11), symmetrically or asymmetrically attached on triphenylene cores, have higher melting and clearing points than those of triphenylene derivatives, TP(OC11H23)3(O2CR)3, (R=C4H9, C5H11, C6H13, C7H15), with the same length of peripheral chains. The triphenylene derivatives with longer peripheral chains have shown mesophase at room temperature. __________ Translated from Chemical Research and Application, 2007, 19(10) (in Chinese)  相似文献   

14.
我们前期的合成和实验发现, 对于一系列含酰胺基支链的苯并菲分子, 其生成的液晶的清亮点的高低与分子间氢键的数目有关. 采用Gay-Berne势模拟液晶分子的双体势, 用量子化学和分子力学相结合的ONIOM (HF/STO-3G: UFF)方法优化含酰胺基支链的苯并菲分子的单体和双体的构型和能量, 从而获得Gay-Berne势的参数. 在此基础上, 根据平均场理论, 解一个关于序参量和温度的积分方程, 求出液晶的清亮点. 计算结果与实验一致, 可以解释清亮点和分子间氢键的关系.  相似文献   

15.
Connecting two discotic mesogens via a spacer not only stabilizes the columnar mesophase but also leads to the formation of glass columnar phase, and therefore improves the physical properties of discotic liquid crystals as organic semiconductor. Here, we report the synthesis of eight diacetylene-bridged triphenylene discotic liquid crystal dimers, [C18H6(OCnH2n+1)4(OMe)O2C-C8H16-C≡≡ C-]2, 3(n), (n = 4-8), [C18H6(OC6H13)5O2C-C8H16-C≡≡ C-]2, 6 and [C18H6(OC6H13)5O-(CH2)m-C≡≡ C-]2, 8(m), (m = 1, 3) by Eglinto...  相似文献   

16.
Synthesis and Crystal Structures of Mercury(II) Iodide Complexes with 3- and 4-Pyridylmethylamino- and 4-Pyridylmethoxy Substituted Cyclophosphazene Ligands Multifunctional cyclophosphazene ligands with 2-, 3-, and 4-pyridylalkylamino- or 4-pyridylmethoxy groups, N3P3(OC6H5)5(NHCH2(C5H4N-2)) ( 1 ), N3P3(OC6H5)5 · (NHCH2(C5H4N-3)) ( 2 ), N3P3(OC6H5)5(NHCH2(C5H4N-4)) ( 3 ) and N3P3(OC6H5)5(OCH2(C5H4N-4)) ( 4 ) are accessible through reactions of monochlorpentaphenoxycyclotriphosphaza-1,3,5-trien with aminomethylpyridine or pyridyl methanolate. 1 does not react with mercury(II) iodide whereas 2–4 yield the metal complexes 2 a , 3 a , and 4 a by interactions of the pyridyl nitrogen atoms. The X-ray single crystal structure analyses of these compounds shows that 2 a and 4 a are dimers, whereas 3 a is a HgI2 polymer with syndiotacticaly arranged ligands.  相似文献   

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