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1.
林惠文  朱文祥 《中国化学》2003,21(8):1054-1058
The structure of the title adduct comprises a phenanthroline derivative 2-phenyl-imidazo[4,5-f]1,10-phenanthroline and a methanol.The composition of the crystalline adduct was characterized as C19H12N4.CH3OH.It belongs to orthorhombic system,space group Pna21 with a=1.3693(4)nm,b=2.2988(7)nm,c=0.51338(15)nm,V=1.6160(8)nm^3.Z=4,and final R1=0.0423.wR2=0.1012 .Crystal structure shows that all the 19 carbon atoms and 4 nitrogen atoms are coplanar.The bond length data indicated that a very extensive conjugation system was formed.This conjugation makes the compound being a potentially excellent energy transformer used for luminescent materials.  相似文献   
2.
Differentkindsofopenchaincrownethershavebeensynthesizedasthemodelcompoundsofionophoresandtheirinteractionswithsodium,potassiumandrareearthionshavealsobeenstudiedl'z.PanshowedCe(III)yieldedalf1complexwithl,8-bis(8'-quinolyloxy)-3,6-dioxaandtheCe(IIl)ioncoordinatedbothtoetheroxygenandquinolinenitrogenatoms3.TUmInleridentifiedtwolanthanidenitratecomplexeshavingastoichiometryof3:2(3RE:2L)'.InordertostUdythefunctionsofbothquinolineandbenzenering,introducedintothepolyetherchain,a1inearpolyether…  相似文献   
3.
Substituted 6-aminopyrano[2,3-c]pyrazoles were synthesized by the two-component condensation of arylidenemalononitriles and substituted 5-pyrazolones or three-component condensation of aromatic aldehydes, malononitrile, and substituted 5-pyrazolones. It was established by X-ray crystallographic analysis that pyranopyrazoles exist in the 2H and not the 1H tautomeric form.  相似文献   
4.
研究了酚醛型吸附树脂在水体系中对吡啶和N,N-二甲基苯胺的静态和动态吸附行为.结果表明,在水中树脂对吡啶和N,N-二甲基苯胺的吸附主要以疏水吸附机理进行;吸附吡啶和N.N-二甲基苯胺的初始阶段,即达到38.3~48.9%平衡吸附时,吸附速率数据和半经验速率方程很吻合:酚醛型吸附树脂等温吸附吡啶和N,N-二甲基苯胺的平衡吸附数据符合Langmuir方程,相关系数在0.99以上,酚醛型吸附树脂吸附吡啶和N,N-二甲基苯胺属单分子层吸附:用80%的乙醇溶液作洗脱剂来洗脱吸附吡啶已达饱和的JDW-2树脂,效果是很理想的.在3.6个床体积内洗脱率达91.52%,4.8个床体积内洗脱率达到94.85%。表明酚醛型吸附树脂具有优良的洗脱性能.  相似文献   
5.
Adducts of four phosphine chalcogenides with the chiral dirhodium complex ([Rh-Rh]) were investigated by variable-temperature 1H and 31P NMR spectroscopy in order to compare their properties as axial ligands. Whereas the selenide (1) and the sulfide (2) are strong ligands with electrostatic attraction and, in addition, a significant orbital (HOMO-LUMO) interaction, the phosphine oxide compounds (P=O) bind primarily via electrostatic attraction and are relatively weak donors. Moreover, the overall bond strength in these adducts depends on steric congestion around the P=O group.  相似文献   
6.
The new tetracyanoborate K[B(CN)4]·CH3CN was synthesized by dissolution of the solvent‐free K[B(CN)4] in acetonitrile and subsequent careful crystallization. The crystal structure has been determined by single‐crystal X‐ray diffraction. It crystallizes in the orthorhombic space group P212121 with Z = 4. Some comparisons with related structures are made, and the vibrational spectrum is discussed.  相似文献   
7.
Diels-Alder adducts of 1,2-dihydropyridine with maleic and acrylic acid derivatives were stereospecifically converted by way of RuO4 oxidation into new r-2,c-3,c-4,c-5-piperidinetetracarboxylic acid, r-2,t-3,t-4,c-5-piperidinetetracarboxylic acid, r-2,c-3,c-5-piperidinetricarboxylic acid, and r-2,t-3,c-5-piperidinetricarboxylic acid.  相似文献   
8.
用定量体积排除色谱方法研究了过渡金属Fe(Ⅲ)、Co(Ⅲ)、Cu(Ⅱ)、Ni(Ⅱ)的乙酰丙酮螯合物在四氢呋喃溶液中的加合和缔合行为。在溶液中乙酰丙酮钴(Ⅲ)以单个螯合物分子的形式存在,乙酰丙酮铜(Ⅱ)和乙酰丙酮铁(Ⅲ)与溶剂加合生成加合物,乙酰丙酮铁(Ⅲ)除加合物外还存在缔合度为2-10的多分散缔合物,乙酰丙酮镍(Ⅱ)水合物在四氢呋喃中产生了加合交换作用,同时存在缔合度为6左右的缔合物。色谱数据给出了螯合物、加合物及缔合物  相似文献   
9.
Addition and Substitution Reactions at Tetrafluoro- and Tetrachlorodiborane(4) From equimolar mixtures of B2F4 and MenN(SiMe3)3-n (n = 0–3) the mono-addition products 1–4 are formed at low temperatures. By elimination of Me3SiF the adduct 2 gives the dimeric monosubstituted diborane 8 , which slowly decomposes at room temperature to the aminoborane 6 and (BF)n. The course of the reactions was studied by means of 11B and 19F NMR spectroscopy and by measuring the vapor pressures. According to the 11B and 31P NMR spectra the reaction of B2Cl4 with PCl5 or [Me4N]Cl in liquid hydrogen chloride at 0°C does not yield [PCl4]2+[B2Cl6]2? or [Me4N]2+[B2Cl6]2? but gives [PCl4]+[BCl4]?, PCl3 and BCl3 or [Me4N]+[BCl4]? and BCl3 besides (BCl)n.  相似文献   
10.
Treatment of allylic alcohols with hexafluoropropene-diethylamine adduct (PPDA) afforded N,N-diethyl-2-fluoro-2-trifluoromethyl-4-alkenamides which were formed by the Claisen rearrangement of intermediary 2-alkenyl-1-diethylamino-2,3,3,3-tetrafluoro-1-propenyl ethers. Although (E)-allylic alcohols gave two diastereomeric products in about 1:1 ratio, (Z)-allylic alcohols gave the corresponding product as a single diastereomer.  相似文献   
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