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31.
选择柔性的双吡啶双酰胺配体N,N'-双(3-吡啶甲酰胺基)-1,2-乙烷(3-bpye)、钼酸铵和氯化锌在水热条件下自组装制备了一个基于一维[H_2Mo_4O_(14)]_n~(2n-)链的三维锌配合物[Zn(3-bpye)(H_2Mo_4O_(14))(H_2O)_2],并通过元素分析、红外光谱、热重分析等技术手段研究了配合物的结构,并利用X射线单晶衍射分析进行了晶体结构表征。结构解析揭示标题配合物是三斜晶系,P-1空间群,晶胞参数a=0.61310(3)nm,b=1.04750(6)nm,c=1.06540(6)nm,α=78.5540(10)°,β=77.5350(10)°,γ=89.9050(10)°,V=0.65420(6)nm~3,M_r=981.47,D_c=2.491 g/cm~3,Z=1,F(000)=468,R_1=0.0290,ωR_2=0.1068。标题配合物中,金属锌离子连接一维[H_2Mo_4O_(14)]_n~(2n-)链形成一种二维无机双金属层[Zn(H_2Mo_4O_(14))]_n,相邻的层间又通过双齿配体3-bpye连接形成三维CdSO_4拓扑的骨架结构。配合物表现出强的荧光发射特性,而且其在紫外光照下对亚甲基蓝和罗丹明B均有明显的催化降解活性。  相似文献   
32.
The reaction of equimolar quantities of trans-[ReOCl3(PPh3)2] and 8-hydroxyquinoline (Hhqn) in benzene led to the isolation of the six-coordinate complex [ReOCl2(hqn)(PPh3)] (1). With 2-pyridine-ethanol (Hhep) the compound [ReOCl2(hep)(PPh3)] (2) was obtained. Both hqn and hep ligands act as monoanionic bidentate N,O-donor chelates. Although the two complexes are very similar, there are some significant differences in certain bond distances and angles in them. Both complexes contain the nearly linear trans O=Re–O axis, with this angle equal to 160.9(2)° and 167.8(1)° in 1 and 2, respectively.  相似文献   
33.
田鹏  高保娇  张妍妍 《应用化学》2010,27(12):1376-1380
以无致癌毒性的1,4-二氯甲氧基丁烷为氯甲基化试剂,先将交联聚苯乙烯(CPS)微球氯甲基化,制得氯甲基化微球CMCPS。 然后使微球CMCPS与4-吡啶甲醛进行季铵化反应,将4-吡啶甲醛键合到CPS微球表面,制得键合吡啶甲醛(PyAL)的改性微球PyAL-CPS。 考察了主要反应条件对季铵化反应的影响,最终确定季铵化反应的优化条件:溶剂CCl4,反应温度60 ℃,最后使改性微球PyAL-CPS、4-吡啶甲醛及吡咯在固-液界面上进行Adler反应,形成固载吡啶基卟啉(PyP)的微球PyP-CPS。 用IR和UV-Vis以及Zn2+配合物生成法表征了微球PyP-CPS的形成及负载量。  相似文献   
34.
The reaction of Hppko (Hppko = phenyl 2‐pyridyl ketone oxime) and CoCl2 · 6H2O in the CH3OH solvent with the presence of triethylamine (NEt3) at room temperature and the exposure to air resulted in the formation of a new pentanuclear, mixed‐valence cobalt complex with the molecular formula [{CoII(CH3O)3}2{CoIII33‐O)(ppko)3}Cl2]. X‐ray single crystal analysis displays a trigonal bipyramid configuration with the terminal two CoII ions wrapping an triangle [CoIII3O]7+ core. The intermolecular C–H ··· O and C–H ··· Cl interactions form a 2D network framework. The analysis of magnetic susceptibility revealed the dominant antiferromagnetic interactions and strong orbital contribution of CoII ions.  相似文献   
35.
Molecular salts, often observed as cocrystals, play an important role in the fields of pharmaceutics and materials science, where salt formation is used to tune the properties of active pharmaceutical ingredients (APIs) and improve the stability of solid‐state materials. Salt formation via a proton‐transfer reaction typically alters hydrogen‐bonding motifs and influences supramolecular assembly patterns. We report here the molecular salts formed by the pyridyl bis‐urea macrocycle 3,5,13,15,21,22‐hexaazatricyclo[15.3.1.17,11]docosa‐1(21),7(22),8,10,17,19‐hexaene‐4,14‐dione, ( 1 ), and naphthalene‐1,5‐disulfonic acid (H2NDS) as two salt cocrystal solvates, namely 4,14‐dioxo‐3,5,13,15,21,22‐hexaazatricyclo[15.3.1.17,11]docosa‐1(21),7(22),8,10,17,19‐hexaene‐21,22‐diium naphthalene‐1,5‐disulfonate dimethyl sulfoxide disolvate, C16H20N6O22+·C10H6O6S22−·2C2H6OS, ( 2 ), and the corresponding monosolvate, C16H20N6O22+·C10H6O6S22−·C2H6OS, ( 3 ). This follows the ΔpKa rule such that there is a proton transfer from H2NDS to ( 1 ), forming the reported molecular salts through hydrogen bonding. Prior to salt formation, ( 1 ) is relatively planar and assembles into columnar structures. The salt cocrystal solvates were obtained upon slow cooling of dimethyl sulfoxide–acetonitrile solutions of the molecular components from two temperatures (363 and 393 K). The proton transfer to ( 1 ) significantly alters the conformation of the macrocycle, changing the formerly planar macrocycle into a step‐shaped conformation with transcis urea groups in ( 2 ) or into a bowl‐shape conformation with transtrans urea groups in ( 3 ).  相似文献   
36.
The reaction of Ag2SO4 and bpp (bpp = 1,3‐bis(4‐pyridyl)propane) in H2O afforded the complex [Ag2(bpp)2(SO4) · 6.5H2O·CH3OH]n, 1. The IR and TGA have been recorded and the structure has been determined. Crystal data for 1: Space group C2/c, a = 17.885(4), b = 25.230(6), c = 8.832(2) Å, β = 105.437(4)°. V = 3841(1) Å3, Z = 8 with final residuals R1 = 0.0710 and wR2 = 0.1620. The complex shows a three‐dimensional supramoleclar structure constructed with two‐dimensional infinite [Ag2(bpp)2]n sheetlike layers pillared by Ag‐Ag interactions and Ag····O (SO4) interactions in the solid state.  相似文献   
37.
A comprehensive theoretical investigation into the mechanism of 1‐phenyl‐1‐(4‐pyridyl)ethene hydroformylation, using a rhodium catalyst employing a nonlocal density functional method (B3LYP), was carried out. The calculated results show that it is strongly exothermic by >90 kJ/mol of the whole catalytic cycle, and the rate‐limited step is H2 oxidative addition. The regioselectivity originates from olefin insertion into the Rh? H bond. The predominant product is the regiospecifically 3‐phenyl‐3‐(4‐pyridal)propanal determined both thermodynamically and kinetically. These are in agreement with practicality experimental studies. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2006  相似文献   
38.
An efficient synthetic method for the preparation of pyridyl‐pyrimidines as potential inhibitors of protein–protein interactions is described. The key transformation is the reaction of a pyrimidine enaminone with phenyl ethyl acetate and NH4OAc to yield the desired pyridyl‐pyrimidine.  相似文献   
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