学科分类
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340 个结果
  • 简介:Using2-bromo-1-methylpyridimiumiodideascarboxylactivatingagent,10ansa-macrolactamswerepreparedconvenientlyfromthecorrespondingseco-precursorw-aminoacidsintheyieldsof78-2%.

  • 标签: LACTAM ansa-macrolactam CYCLIZATION lactamization.
  • 简介:Copper-dopedZnOnanoparticlesweresynthesizedbythesol-gelmethod.TheX-raydiffraction(XRD)resultshowsthatZn1-xCuxO(x≤0.04)samplesaresinglephasewithZnO-likewurtzitestructure,whilethesecondaryphaseCuisobservedinaZn0.95Cu0.05Osample.MagneticmeasurementsindicatethatZn1-xCuxO(x≤0.04)samplesareferromagneticatroomtemperature.Astronggreenpeak(520nm)wasobservedexceptforUVbandpeakinphotoluminescent(PL)spectrumofZn0.98Cu0.02O.

  • 标签: ZNO纳米粒子 纤锌矿结构 溶胶凝胶法 组分 性能 X射线衍射
  • 简介:4,5-Diphenyl,4,5-di(4-methylphenyl),4,5-di(4-methoxyphenyl)-2-(2,5-dimethylthioph-en-3-yl)imidazolesweresynthesized.Oxidationoftheobtainedimidazoleswithpotassiumferricyanideinwater-alcoholsolutionofalkaligavethecorrespondingdimers.ThestructureswerecharacterizedbyIR,1HNMR,massspectroscopyandelementalanalysis.Thedimersshowedphotochromisminsolutiononirradiation.

  • 标签: SYNTHESIS IMIDAZOLES dinners PHOTOCHROMISM
  • 简介:采用HF/DFT的混合泛函PBE0和UPBE0优化了配合物[Os(PH3)2(CN)2(N^N)](其中N^N=2,2′-吡啶)的基态和激发态结构.在基态和激发态结构的基础上,利用含时密度泛函理论(TD-DFT)方法,结合极化连续介质(PCM)模型分别计算了它在二氯甲烷(1)、甲醇(2)、气态(3)和乙腈(4)溶液中的吸收和发射光谱.研究结果表明:优化得到的几何结构参数和相应的实验值符合得非常好.在极性较大的溶剂(2和4)中Os—P(1)和Os—C(1)键较长,Os—N(3)键较短,溶剂的极性会影响配合物的电子云分布.配合物在1-4溶剂中的最低能吸收和发射均来自分子轨道68→71的激发,该激发被指认为[d(Os)+π(CN)+π(N^N)→π*(N^N)]的跃迁具有混合的MLCT/LLCT特征.配合物在1-4溶剂中的最低能吸收和发射分别在471,410,488和445nm以及598,536,634和545nm,表明随着溶剂极性的逐渐增大(31〈4〈2),最低能吸收和发射发生明显的蓝移.这显示出通过改变溶剂极性可以调节配合物的发光颜色.

  • 标签: Os配合物 PBE0泛函 电子结构 溶剂化显色效应
  • 简介:Ahomologousseriesof4’-methylphenyl4"-[(4-alkoxy-2,3,5,6-tetrafluorophenyl)ethynyl]-benzoateshavebeensynthesized.Polarizingmicroscopictexturalobservationshowsthatsuchcompoundsexhibitenantiotropicnematicphase.

  • 标签: Liquid crystal 1 4-tetrafluorophenylene SYNTHESIS NEMATIC
  • 简介:Aseriesofethyl6-alkoxy-7-phenyl-4-hydroxy-3-quinolinecarboxylatesweredesignedandsynthesized.Theirstructureswereconfirmedby~1HNMR,~(13)CNMR,IRandHRMS.ThebiologicalactivitieswereprimarilyevaluatedagainstEimeriatenellaaccordingtoAnticoccidialIndex(ACI)methodinvivo.Theresultsshowedthatcompounds5e,5fand5iexhibitedanticoccidialactivitiesagainstE.tenellaat27mgkg~(-1).

  • 标签:
  • 简介:DBUH-Br3catalyzedselectiveconversionofsulfidestosulfoxidesinthepresenceofH2O2asoxidizingagentisdescribed.Thereactionwasperformedselectivelyatroomtemperatureandrelativelyshortreactiontimes.

  • 标签: H2O2 ROOM temperature short agent
  • 简介:Theorientationoftheadditionof5-amino-3-benzylthio-1,2,4-triazoleanditsanalogues(pyrazole)(1)withthearylisocyanatecanbedirectedbycontrollingthereactiontemperatureandoneoftheproduct,5-amino-1-arylaminocarbonyl-3-benzylthio-1,2,4-triazole(pyrazole)(2),canrearrangeat170Ctoanotherproduct,5-arylureylene-3-benzylthio-1,2,4-triazole(pyrazole)(3).Aplausiblemechanismexplanationforthisrearrangementreactionwaspresented.Itwassuggestedthattherearrangementreactioncouldbereferredtothethermodynamicstranspositionleadingtothepredominant5-arylureylene-3-benzylthio-1,2,4-triazoleenergypreferentially.

  • 标签: 1 2 4-Triazole ary ISOCYANATE REARRANGEMENT
  • 简介:在这个工作,它被介绍任务的应用象对3-amino-5-aryl-2,5-dihydropyridazines的合成的可溶的支持咸的特定的onium。这可溶的支持具有宽适用性并且没有它的限制,溶液阶段化学把稳固的阶段合成的优点与那些相结合。在一个简单的洗步骤以后,产品从支持被劈开并且在好收益获得了。

  • 标签: 固相合成 可溶性 氨基 芳基 鎓盐 适用性
  • 简介:采用点群链R(3)OD3关系来标记D3点群的斯塔克能级.基于双层点电荷配位场(DSCPCF)和经典的简单点电荷配位场(PCF)两种模型,利用自编的计算程序,对三角对称(D3)掺杂晶体YAB:Eu中Eu^3+离子的配位场微扰能级进行理论计算和归属.通过与实验能级比较,结果表明:按照配合物的实际配位结构,利用较少的拟合参数,PSCPCF模型得到比PCF模型更为合理的能级分布和精确的能级分裂值.

  • 标签: 稀土配合物 YAB∶Eu 配位场分析
  • 简介:Halfsandwichirondicarbonylcomplex[η5-C5H3(t-Bu)2]Fe(CO)2Cl(1)reactswith1,2-dilithiumdiselenocarboraneLi2Se2C2B10H10(2)togiveabinuclearironcarboranecomplex[η5-C5H3(t-Bu)2]2Fe2(CO)3*Se2C2B10H10(3).TheX-raydiffractionanalysisofcomplex3revealsthatoneoftheironatomsischiral.

  • 标签: Carborane Halfsandwich IRON complex Chirality Molecular
  • 简介:ThepossiblegeometricalstructuresandrelativestabilitiesofsemiconductormicroclustersGa.P.(n=1-4)werestudiedbyvirtueofdensityfunctionalcalculationswithgeneralizedgradientapproximation(B3LYP).ForthemoststableisomersofGa,,P.(n=1-4)clusters,theelectronicstructure,vibrationalproperties.dipolemoment,polarizabilityandionizationpotentialwereanalyzedbymeansofHF.MP2.CISDandB3LYPmethodswithdifferentbasissets.

  • 标签: 半导体 磷化镓 电子结构 稳定性 偶极矩 振动性能
  • 简介:HAND ̄(13)CNMRSTUDYOFINCLUSIONCOMPLEXATIONOFDSSWITHβ-CYCLODEXTRIN¥QingXiangGUO;TanREN;ZiZhongLIandYouChengLIU(NationalLabora...

  • 标签: 13C NMR
  • 简介:1,2-Diarylacetylenes被与乙酰氯化物和结果的ethene氯化物的消除由diaryl酉同类的增加组成的一个灵巧的方法综合了。在1,2-diarylacetylene的物理性质和结构之间的关联被微分扫描学习了热量计(DSC),折射媒体和电镀物品光的参数测试仪器。结果证明birefringence与把cyclohexyl插入到骨骼,而是mesophase范围被增加,融化并且变清点与在分子,和birefringence介绍乙烯桥被减少,粘性,空地点和mesophase变化都能与perfluoroalkyl/alkoxyl终端被减少而不是alkyl/alkoxyl一半。

  • 标签: 合成 1 2-二芳乙酰烯 相关性 结构 物理性质 环己基
  • 简介:Thecrystalstructureoftetrakis[(pyrrol-1-yl)methyl]methanewasdeterminedbyX-raydiffractionmeasurement,andtheresultshowsthatitbelongstomonocliniccrystalsystem,spacegroupisP21/n,witha=0.9284(3)nm,b=1.0950(6)nm,c=1.8749(8)nm;α=γ=90.00(4)°,β=103.63(3)°,V=1.8523(14)nm3,Z=4,ρcalcd.=1.192kg/m3,μ=0.072nm-1,F(000)=712,R1=0.0854,wR2=0.1884.Ithasbeenfoundthatthemoleculesexistintwoenantiomericstates.Enantioselectiveself-assembliessuchasone-dimensionalmolecularstacksinasinglehandedness,homochiralmonolayersandachiralsuperlatticearespecifiedinthisracemiccrystal.Inaddition,asimpletechniqueisadvocatedtodistinguishchiralstatesfromtetrahedralmoleculesinthesolidstate.ThepresentR/Snomenclatureofthetetracooradinatedcarboncentersisusedsolelyforitsconveniencetodistinguishthetwoenantiomericstates,butnotusedtodeterminetheabsoluteconfigurations.

  • 标签: 分子 手性特征 手性超点阵 四(吡咯基甲基)甲烷 外消旋晶体 对映选择性自组装
  • 简介:开发HIV-1熔化的口头上地可得到的小分子禁止者在许多年吸引了重要兴趣。司丰饶最近报导了试验性地被显示在低micromolar范围禁止房间房间熔化的几合成混合物。我们执行了计算学习帮助由在gp41上停靠这些混合物到恐水病的衣袋上识别可能的有约束力的模式并且描绘有约束力的建筑群的结构。详细gp41分子绑定相互作用和绑定的免费精力通过分子的动力学模拟和MM-PBSA计算被获得。在gp41禁止者建筑群的特定的分子的相互作用被识别。现在的计算学习补充相应试验性的调查并且帮助为小分子的gp41禁止者的进一步的精炼建立一个好起点。

  • 标签: GP41 抑制剂 小分子 HIV 计算 分子动力学模拟
  • 简介:CASnanoparticleswereassembledonthesmoothsurfaceofapieceofsilverbyusing1,4-benzenedithiolascouplingmolecules.TheSEMandresonanceRamanspectroscopiccharacterizationsdemonstratethatthenanosizedstructureofCdSwasstillpreserveduponassembly,andatwo-dimensionalstructureofCdSnanoparticleswasformedonthesubstratesurface.TheFT-Ramanspectraindicatethat1,4-benzenedithiolwascoupledbetweenCASnanoparticlesandthesilversurfacewithatiltedorientation.TheRamanscatteringof1,4-benzenedithiolwassubstantiallyenhancedbytheassembledCdSnanoparticles,probablyduetothealterationofthepolarizabilityof1,4-benzenedithiolandtheelectromagneticinteractionbetweenthedipolesoftheCdSparticlewithitsimageinthemetalsubstrate.

  • 标签: 硫化镉 半导体纳米微粒 自组装 拉曼散射 拉曼光谱 银表面