Molecular Recognition Study on a Supramolecular System. Part 21. Inclusion Complexation Thermodynamics of Aliphatic Alcohols by Organoselenium Modified β-Cyclodextrins

The spectrophotometric titrations have beenperformed at 25–40 °C in aqueous solution to give the complexstability constants and the thermodynamic parametersfor the stoichiometric 1 : 1 inclusion complexation ofvarious aliphatic alcohols withmono[6-(phenylseleno)-6-deoxy]--cyclodextrin (2),mono[6-(o-, m-,p-tolylseleno)-6-deoxy]--cyclodextrin (3–5),mono[6-(p-chloro-phenyl-seleno)-6-deoxy]--cyclodextrin(6), mono[6-(benzylseleno)-6-deoxy]--cyclodextrin (7) and mono[6-(naphthaleneseleno)-6-deoxy]--cyclodextrin(8). On thebasis of the present and previous results, themolecular binding abilities and selectivities forguest aliphatic alcohols of the host -cyclodextrinderivatives (2–8) are discussed comparatively and globallyfrom the thermodynamic point of view. Thethermodynamic parameters obtained are criticalfunctions of the size/shape of aliphatic alcohols, andthe position and type of the substituent introduced tothe aromatic ring of -cyclodextrin's sidearm,which are elucidatedin terms of the conformational, electrostatic,hydrogen-bonding, and hydrophobic effects.     

共轭高分子的研究——Ⅶ.脂肪腈类的聚合

<正> 聚腈作为新的一类共轭高分子而引起注意。本文在前报的基础上进一步选择了一系列脂肪腈(乙腈、丙腈、戊腈、庚腈和苯乙腈),系统地研究它们在络合能力较强的付氏试剂(BF_3和TiCl_4等)作用下的聚合反应与机理,同时测定了各聚腈的物理性能。 1.腈的络合聚合 腈类与付氏试剂可形成定组成的络合物结晶:     

Synthesis of a new class of conformationally rigid phosphino-oxazolines: highly enantioselective ligands for Ir-catalyzed asymmetric hydrogenation

[reaction: see text] A new class of conformationally rigid phosphino-oxazoline ligands were synthesized from readily available enantiopure phenyl glycinol. Ir complexes with these ligands are air-stable and highly enantioselective catalysts for asymmetric hydrogenation of aryl alkenes and alpha,beta-unsaturated esters in up to 99% ee.     

四磺酸基酞菁锌在水和非水溶剂中的电化学性质研究

在非水溶剂（二甲基亚砜（ＤＭＳＯ）及Ｎ,Ｎ＿二甲基甲酰胺（ＤＭＦ））中的伏安曲线．呈现三对电流峰,表明存在三个可逆或准可逆酞菁配体的单电子转移过程,而在水溶液中则不呈现准可逆行为,且波形改变很大．此外,还比较了四磺酸基酞菁锌的水溶液在自然光和红光（６００～７００ｎｍ）照射下的循环伏安曲线,其氧化还原峰的数目和峰电位基本不变,但在红光照射下比自然光照射下的峰电流明显增大．     

Raman mapping and in situ SERS spectroelectrochemical studies of 6-mercaptopurine SAMs on the gold electrode

The self-assembled monolayers (SAMs) of 6-mercaptopurine (6MP) were formed at the roughened polycrystalline gold surfaces in acid and alkaline media. The time-dependent Raman mapping spectral analysis in conjunction with the quantum calculations for the vibrational modes using ab initio BLYP/6-31G method suggested that both of the resulted 6MP SAMs adopted the same adsorption mode through the S atom of pyrimidine moiety and the N7 atom of the imidazole moiety anchoring the gold surface in a vertical way. The in situ surface-enhanced Raman scattering spectroelectrochemical experiment was conducted to examine the stability of the SAMs at various bias potentials. It was found that the detaching process of the 6MP SAMs from the surface involved one electron reduction as the voltage was applied at ca. 0.7 V vs a standard calomel electrode.     

<Emphasis Type="Italic">Ab initio</Emphasis> study of small coinage metal telluride clusters Au<Subscript>n</Subscript>Te<Subscript>m</Subscript> (<Emphasis Type="Italic">n,m</Emphasis> = 1, 2)

The geometries of the most stable isomers of gold telluride systems AuTe, Au₂Te, and AuTe₂ are determined using the MP2 method. The aspect of gold—telluride interaction, the electron correlation, and relativistic effects on geometry and stability are investigated at the MP2 and CCSD(T) theoretical levels. The results show that the electron correlation and relativistic effects are responsible not only for gold—gold attraction but also for additional gold—telluride interaction. The gold—telluride interaction is strong enough to modify the known pattern of bare gold clusters. Both effects are essential for determining the geometry and relative stability of this type of systems.     

Synthesis and biological activity of novel 2-(3-trifluoromethylphenoxy)-4-trifluoromethylthiazole-5-carboxamide derivatives

Novel 2-(3-trifluoromethylphenoxy)-4-trifluoromethylthiazole-5-carboxamides were designed and synthesized utilizing ethyl 3-amino-4,4,4-trifluoro-2-butenoate as a starting material via six steps. Subsequently, their biological activities were evaluated in the greenhouse. Results indicated that several compounds have some insecticidal or fungicidal activity at 600 g ai/ha and 300 g ai/ha, respectively.     

三元无规芳—脂族聚酯酰胺的热致液晶行为

采用低湿溶液缩聚的方法合成了对苯二甲酰氯，二甲基联苯胺和己二醇为单体的芳酯族液晶聚酯酰胺。用ＤＳＣ，Ｘ光衍射分析和偏光显微镜等手段研究了该系列聚酯酰胺的热致液晶行为，确认了二甲基联苯胺单体用量在２０％（ｍｏｌ）的情况下，所得聚酯酰胺仍为向列型液晶聚合物。由于聚酯酰胺分子间聚酰胺链段之间的氢键作用，随着二甲基联苯胺用量增加至６０ｍｏｌ％时，所得的聚酯酰胺己无液晶转变温度，其液晶区间即从熔融温度直至分