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1.
近晶A相;新型三噻吩衍生物的合成及其液晶性能  相似文献   

2.
Two novel porphyrin derivatives, 5,10,15,20-tetra(4-(N-octane-carboxamide)phenyl)porphyrin (4NC8-TPP) and 5,10,15,20-tetra(4-(N-stearyl-carboxamide)phenyl)porphyrin (4NC18-TPP), were synthesized. Their molecular structures were characterized by means of time-of-flight mass spectrometer (TOF-MS), nuclear magnetic resonance (NMR), and infrared spectra (IR). The thermal behavior and morphologies of 4NC8-TPP and 4NC18-TPP were examined by thermal gravity (TG), differential scanning calorimetry (DSC), x-ray diffraction (XRD), and polarizing optical microscope (POM). It was found that both 4NC8-TPP and 4NC18-TPP had mesogenic properties.  相似文献   

3.
The relationships between electronic structures and spectra properties are investigated by DFT/TDDFT for terthiophene derivatives, BMA‐3T (tri‐aryl amine end‐capped terthiophene), BBA‐3T (tri‐aryl amine and tri‐aryl boron end‐capped terthiophene) and BPB‐3T (tri‐aryl boron end‐capped terthiophene). The calculated results show that BMA‐3T, BBA‐3T and BPB‐3T have higher HOMO energy level and lower ionization potentials (IPs) than 3T. BMA‐3T has good hole injection ability and hole‐transport property as reported in experiment. The designed molecule of BBA‐3T and BPB‐3T own lower LUMO level and higher electron affinities (EAs) than BMA‐3T, which facilitate electron injection and improve their electron‐transport properties. Surprisingly, BPB‐3T has preferable charge equilibrium property since its hole reorganization energy (λh) is close to electron reorganization energy (λe). The ΔE (HOMO−LUMO) and Eg of these three derivatives are narrower compared to 3T, and the absorption as well as emission spectrum exhibited red‐shifts.  相似文献   

4.
韩杰王彦美  王晓光 《中国化学》2006,24(11):1594-1598
Two series of 2,5-disubstituted thiophene derivatives (series 1: 2,5-bis(p-alkoxyphenylethynyl)thiophene and series 2: 2,5-bis[p-(p-alkoxyphenylethynyl)(phenylethynyl)]thiophene) were synthesized and characterized by ^1H NMR, ^13C NMR, HRMS and elemental analysis. The relationship between the structure and the mesogenic and spectroscopic properties has been discussed. The results show that compounds 1a-1f all exhibited an enantiotropic nematic mesophase, which was confirmed by the polarized optical microscopy (POM), differential scanning calorimeter (DSC) and variable temperature powder X-ray diffraction (PXRD). In contrast, the extended conjugated analogues 2a-2b had no liquid crystal properties. As for the spectroscopic properties, incorporating more phenylethynyl units results in red-shifted absorption and emission spectra, greatly enhanced quantum efficiency.  相似文献   

5.
The photochromic compounds continue to attract significant attention in view of their general applicability as optical information storage materials or switching devices1-2.In order to develop novel bifunctional and multifunctional materials,special attention has been paid to photochromic liquid crystalline compounds.Many studies have been carried out for all kinds of mixed systems,which are to dope small amounts photochromic compounds into liquid crystal3-4.However,the combination of the prop…  相似文献   

6.
聚吡咯衍生物的合成及液晶性能   总被引:1,自引:0,他引:1  
系统论述了新型导电功能性液晶聚合物3-和N-液晶基元取代聚吡咯的合成和液晶行为。指出通过化学氧化聚合、电化学氧化聚合和脱卤缩合聚合可以获得液晶性聚吡咯衍生物。它们均显示热致液晶行为,且多数呈现近晶液晶相,少数呈现向列液晶相,有些具有2种近晶相,有些具有单变液晶性。N-液晶基元取代聚吡咯比3-位取代聚吡咯具有较高的液晶稳定性。较长的亚甲基间隔和极性的介晶基团能够使N-取代聚吡咯具有较大的液晶微区和稳定的液晶相。N-取代液晶聚吡咯在摩擦力的作用下还可以诱发单轴取向。这种热致液晶性聚吡咯衍生物的研究成功有希望克服聚吡咯难以成型加工的巨大障碍。  相似文献   

7.
以苯并噻唑、苯乙酰基和吡啶阳离子为电子受体,二乙烯基苯为共轭桥,合成了两个新的A-π-A′型苯并噻唑衍生物:4-(2-苯并噻唑)-乙烯基查尔酮(1)和4-{4-[2-(苯并噻唑)乙烯基]苯乙烯基}-N-甲基吡啶碘盐(2).研究了它们在溶液和固体基质中的光物理性质.研究发现:染料2由于具有较强的极性和较好的平面性,从而具有较长的吸收、发射峰和较强的荧光发射.有机染料在聚甲基丙烯酸甲酯/溶胶-凝胶复合玻璃中的发光行为与聚甲基丙烯酸甲酯和溶胶-凝胶玻璃二者的基质性质有关,同时由于固体基质中分子发生聚集的可能性降低,荧光强度相对于同浓度溶液增强,稳定性提高.  相似文献   

8.
合成了中心桥键为酯基和Schiff碱基连接且分子中含4个苯环的17个化合物,其中有带支链和不带支链的化合物,化合物的结构通过IR,NMR和元素分析进行表征,其介晶性通过DSC和偏光显微镜进行研究.讨论了取代基对介晶性的影响.结果表明,该类型结构的二茂铁化合物绝大多数具有液晶性,取代基对介晶性的影响较小.  相似文献   

9.
新型双吲哚马来酰亚胺衍生物的合成   总被引:1,自引:0,他引:1  
以1-(3-氧代四氢吡喃丙基)-吲哚-3-乙醛酸甲酯(5)和吲哚-3-乙酰胺(6)为原料,在催化剂叔丁醇钾的四氢呋喃溶液存在下发生偶合反应,经浓盐酸处理得脱保护的中间体7,再经甲磺酰化反应、氨解反应得到4种新的具有不同氨烷基侧链的双吲哚马来酰亚胺衍生物9a,9b,9d,9e.目标产物结构通过1H NMR,13C NMR,MS和HRMS确证.  相似文献   

10.
朱晓东  顾为  聂爱华 《合成化学》2013,21(3):309-312
以7-羧基喹啉为原料,经硝化、酯化、喹啉环和硝基的还原、磺酰化和烷基化反应合成了7个新型的甲磺酰基喹啉衍生物,其结构经1H NMR和LC-MS表征。  相似文献   

11.
新型低聚噻吩衍生物的设计、合成及其液晶性能的研究   总被引:3,自引:0,他引:3  
设计、合成了一系列新型低聚噻吩衍生物N,N’-双烷烃基-5,5’-二溴基-2 ,2’:5’,2’-三噻吩-4,4’-二酰胺[N,N’-dialkyl-5,5’-dibromo-2,2’:5 ’,2’-terthiophene-4,4’-dicarboxamide](DNCnDBr3T,n=5,8,6,18)。示差扫描 量热法(DSC)测定的结果及偏光光学显微镜观察的结果显示,DNC18DBr3T, DNC16DBr3T,DNC8DBr3T具有近晶A形液晶性质,DNC5DBr3T不具有液晶性质。为了探 讨分子间氢链对液晶形成的影响,设计、合成了新型低聚噻衍生物4,4“-双烷烃 酯-5,5“-二溴基-2,2’:5’,2’-三噻吩[4,4’-bis(alkyloxycarbonyl)-5,5’ -dibromo-2,2’:5’,2’-terthiophene](DOCnDBr3T,n=5,8,16,18).测定和观察的 结果发现,DOCnDBr3T(n=5,8,16,18)不具有液晶的结果。这个结果表明,酰胺基 的存在于液晶的形成起着重要的作用。测定DNC18DBr3T在结晶状态和液晶状态下的 红外光谱,进一步证实了部分分子间氢键对于液晶的形成起着重要的作用。  相似文献   

12.
萘甲基苯并咪唑衍生物的合成、表征及其杀菌活性   总被引:6,自引:0,他引:6  
萘甲基苯并咪唑衍生物的合成、表征及其杀菌活性;萘甲基苯并咪唑衍生物; 合成; 晶体结构; 杀菌活性  相似文献   

13.
A new series of 1-alkyl-2-oxo-1,2-dihydro-pyrimidine-5-carboxalic acid amides is described. The reaction of N-((E)-3-(dimethylamino)-2-formylacryloyl) formamidine, an intermediate obtained by Vilsmeier–Haack formylation of acetonitrile with various mono-substituted ureas, provides such compounds in good yields.  相似文献   

14.
A novel, efficient one‐pot approach for the synthesis of furopyrimidine and oxobenzofuran derivatives 4 by a multicomponent reaction of an isocyanide, an aldehyde, and a CH‐acid compound in CH2Cl2 is reported (Scheme 1 and Table). The reactions were completed after 20 h at room temperature. This method has the advantages of high yields, simple methodology, and easy workup.  相似文献   

15.
设计合成了新的甲氨蝶呤(methotrexate, MTX)衍生物14, 在这些新化合物中, 将MTX分子中10-位对氨基苯甲酰谷氨酸砌块移植到4-位, 同时在6-位引入苯环芳香基以及甲基等基团. 生物活性测试结果显示, 化合物14具有与MTX相似的抑制iNOS活性的作用; 相对于MTX, 选测的化合物24明显地增强了抑制K-562白血病细胞株生长的活性. 本研究为进行MTX的结构修饰开辟了新途径, 2-氨基-4-[N-(对氨基苯甲酰谷氨酸)-基]-6-取代基蝶啶衍生物可成为潜在的抗肿瘤候选药物被进一步研究.  相似文献   

16.
17.
以邻、间、对-二茂铁苯胺为原料, 合成了含噻酚的二茂铁苯基席夫碱衍生物并还原得到N-2-亚甲基-噻酚-二茂铁基芳胺衍生物,通过元素分析,IR,UV,1H NMR和X-射线单晶衍射等分析手段,确证了标题化合物的组成和结构,单晶结构解析表明,化合物2c属于单斜晶系,P2/n空间群。量化计算结果证明,化合物2c在晶体中的结构并不是它的最稳定结构;其HOMO轨道主要由Fe原子及茂环上C的原子轨道组成的;电化学实验证明所得邻、间、对化合物的电化学性质相似,氧化还原峰对应于二茂铁的氧化还原过程,Fc+ + e-←→Fc;说明化合物中的二茂铁基所处的化学环境相同,苯环上取代基位置的不同,对化合物在电极表面的扩散系数影响不大, 但对反应速率常数则有较大的影响。  相似文献   

18.
二茂铁Schiff碱型金属有机液晶的合成、结构及介晶性   总被引:10,自引:3,他引:7  
胡平  赵可清  张良辅 《合成化学》1998,6(4):438-441
通过相转移催化剂作用下的二茂铁芳基化反应,合成了p-硝基苯基二茂铁(Ⅰ)。用Sn还原Ⅰ得到4-二茂铁基苯胺(Ⅱ),Ⅱ与p-烷氧基苯甲醛缩合,合成了二茂铁Schif碱型配合物Ⅲ1~Ⅲ7。配合物结构经IR,1HNMR和元素分析确证。DSC和偏光显微镜研究结果显示,该类配合物具有较好的稳定性,并在较低的温度出现介晶相。相转变温度随末端C原子数的增加而呈稳定下降趋势。  相似文献   

19.
A novel biphenyl side-chained diamine with alkyloxy spacer and alkyloxy tail,4'-butoxy-4-(3,5-diami-nobenzoyloxy)hexyloxybiphenyl(C6BBC4),was synthesized and characterized by FTIR and 1H NMR.A series o...  相似文献   

20.
Forty-six novel 3,7-dihydro-purine-2,6-dione derivatives (substituted xanthines) with great structural diversity were synthesized for biological activity screening. Three series of substituted xanthine analogs have been prepared in moderate to excellent yields.  相似文献   

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