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1.
以1,4-二溴苯和1,8-二碘联苯为原料分别与咔唑发生乌尔曼偶联反应制得两种相应的成对偶联分子,用NBS作为溴化试剂与这两种分子反应制得新型的多溴代产物:3,3′,6-三溴-1,4-双咔唑基苯、3,3′,6,6′-四溴-1,4-双咔唑基苯和3,3′,6-三溴-1,8-双咔唑基联苯.该溴化物与咔唑在铜催化下发生乌尔曼偶联反应制得3种新颖的树枝状咔唑类衍生物:3,3′,6-三(N-咔唑基)-1,4-双咔唑基苯、3,3′,6,6’-四(N-咔唑基)-1,4-双咔唑基苯、3,3′,6-三(N-咔唑基)-1,8-双咔唑基联苯.通过核磁、质谱分别对所合成的化合物进行了表征.  相似文献   

2.
以3-氨基-N-苯基咔唑为起始原料,经溴化反应、Suzuki偶联反应和Buchwald偶联反应合成了5,11-二氢-5-苯基吲哚并[3,2-b]咔唑,通过~1H NMR对化合物结构进行了表征.研究了反应温度、催化剂用量以及反应时间等因素对产物收率的影响,得到了最佳反应条件:反应温度100℃,反应时间18 h,催化剂用量为3-氨基-N-苯基咔唑摩尔量的4%.  相似文献   

3.
以咔唑为原料,经溴乙烷的烷基化、NBS的溴化,得到3,6-二溴-9-乙基咔唑3,然后与噻吩硼酸偶联和Vils-meier-Haack反应,得到一种新型咔唑衍生物5.化合物5是一种制备染料敏化太阳能电池中染料的重要中间体,经IR及NMR表征表明结构正确.  相似文献   

4.
以咔唑为起始原料,经Ullmann反应、溴化反应、Miyaura反应和Suzuki反应合成了 9-[1,1'-联苯]-3-基-3-(9,9'-螺二[9H-芴]-3-基)-9H-咔唑,重点研究了不同的溶剂、碱和催化剂对Suzuki反应中目标产物产率的影响.条件优化实验结果表明:在二氯二叔丁基-(4-二甲基氨基苯基)磷钯(...  相似文献   

5.
以邻溴硝基苯为起始原料,依次与双(频那醇合)二硼,对溴苯甲醚经Suzuki-Miyaura反应合成了2-硝基-4’-甲氧基联苯,然后经亚磷酸三乙酯还原反应,三溴化硼催化脱甲基化合成了目标产物2-羟基咔唑,总收率68.9%.通过1 HNMR、13 C NMR表征了合成化合物结构.  相似文献   

6.
以咔唑和苄氯为原料,在温和条件下与N-溴代丁二酰亚胺反应得到了中间体3,6-二溴-9-苄基咔唑。从此中间体出发,经Heck反应合成了具有C2v对称性的9-苄基-3,6-二[2-(吡啶-4-基)-乙烯基]咔唑(BPyVC)。采用核磁共振、红外、质谱等手段确定了新化合物的结构,并对化合物的光物理特性进行了评价。双光子聚合实验的结果表明,BPyVC在扫描速度为22mm/s时的双光子聚合的最低能量密度低于92.7kJ/cm2,在固定光强为12.7mW时,引发双光子聚合的最少曝光时间低于1.15ms。  相似文献   

7.
五氟苯和五氟溴苯是公认的代表性的含氟化合物,可以通过多种反应与其它化合物相连接。N-芳化杂环化合物例如咔唑和吲哚是具有空穴传输性能、在紫外光范围有很强的吸收并且具有发可贵的蓝光等特性。以咔唑为侧基的非共轭类聚合物具有很好的光学性能和空穴传输性能。呋喃噻吩齐聚物具有优异的性质。该文发展了合成咔唑-呋喃-噻吩以及吲哚-呋喃-噻吩齐聚物的方法。以自制的五氟苯代吲哚和五氟苯代咔唑为起始原料,与硼试剂反应分别制备相应的硼酸酯。通过溴封端的噻吩-氟代呋喃-噻吩中间体与硼酸酯反应制备咔唑-呋喃噻吩以及吲哚-呋喃-噻吩齐聚物。  相似文献   

8.
采用溴化反应和乌尔曼偶联反应合成了无定形N-乙基咔唑树状分子.运用密度泛函理论(TD-DFT),在B3LYP/6-31G(d,p)水平上,通过理论计算得到分子的HOMO能级为-5.16eV、LUMO能级为-1.59eV,与实验值非常接近.对N-乙基咔唑树状分子的光物理性能进行了研究,发现化合物在292nm处产生最大吸收峰,其最大发射峰在394nm处.利用循环伏安法对化合物的电化学性能进行了分析,发现N-乙基咔唑树状分子产生了可逆的双氧化峰,起始氧化势为0.74V.N-乙基咔唑树状分子的双光子吸收截面为13.86×10-50cm4.s.(photon)-1.  相似文献   

9.
以对叔丁基杯[n]芳烃1a-1c(n=4,6,8)和间苯二酚杯芳烃1d-1e(R=C6H5,p-HOC6H4)为原料,在碳酸钾存在下以丙酮为溶剂与1-溴-3-氯丙烷反应,得到下缘为氯丙基取代的杯芳烃衍生物2a-2e。进一步以2b-2d为原料,在碳酸钾存在下以丙酮为溶剂与咔唑反应,得到丙基桥连的杯芳烃咔唑衍生物3a-3c。通过红外光谱,核磁共振氢谱等确定了上述产物的结构。  相似文献   

10.
无定形N-乙基七咔唑树状分子通过溴化反应和乌尔曼偶联反应合成。运用密度泛函理论(TD-DFT),在B3LYP/6-31G(d,p)水平上,理论计算出分子的HOMO、LUMO能级。对七咔唑的光物理性能进行了研究,化合物在292nm产生最大吸收峰,最大发射峰在393nm。利用循环伏安法对化合物的电化学性能进行了研究,七咔唑产生可逆的双氧化峰,起始氧化势为0.74V.七咔唑的双光子吸收截面为13.86GM.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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