含有稠环侧链的聚硅氧烷的合成及其对加成型高温硫化硅橡胶性能的影响

将含有多乙烯基的聚硅氧烷与菲式环戊二烯酮和苊式环戊二烯酮分别在α-氯萘中进行Diels-Alder反应,生成含有稠环侧链的聚硅氧烷.该聚硅氧烷具有较好的耐热性.将其作为组分制成高温加成型硅橡胶,综合性能达到较高水平(高模量).随着其用量的增加,可使其耐热性能得到较大改善。     

Vibrational spectra and structure of trinitromethane

The vibrational spectrum of trinitromethane was interpreted in terms of the additive interatomic interaction model on the basis of experimental infrared and Raman spectra of HC(NO₂)₃, DC(NO₂)₃, HC(¹⁵NO₂)₃ and normal coordinate analysis. The frequency assignment results were used in discussing its structure. It was shown that the symmetry of trinitromethane is below C₃ in the liquid state.     

类水滑石及其杂多阴离子柱撑物的合成与表面酸性研究

合成了一些类水滑石和过渡金属取代型杂多酸盐，并由此制备了相应杂多阴离子柱撑水滑石层柱材料。用ＸＲＤ，ＩＲ和元素分析等手段对合成产物进行组成和结构表征，用ＮＨ３－ＴＰＤ，Ｐｙ－ＩＲ研究了合成产物的表面酸性和酸类型，并在异丙醇反应中考察了合成物的酸碱催化行为，结果表明，水滑石和柱撑水滑石均同时存在酸碱中心，且酸碱相对强度与柱阴离子类型密切相关。杂多阴离子进入水滑石层，同时改变了水滑石和杂多酸盐的酸强度     

Rare Earth-Rich Indides <Emphasis Type="Italic">RE</Emphasis><Subscript>5</Subscript>Pt<Subscript>2</Subscript>In<Subscript>4</Subscript> (<Emphasis Type="Italic">RE</Emphasis> = Sc,Y, La–Nd,Sm, Gd–Tm,Lu)

Summary. The isotypic indides RE ₅Pt₂In₄ (RE = Sc, Y, La–Nd, Sm, Gd–Tm, Lu) were synthesized by arc-melting of the elements and subsequent annealing. They were investigated via X-ray powder diffraction. Small single crystals of Gd₅Pt₂In₄ were grown via slow cooling and the structure was refined from X-ray single crystal diffractometer data: Pbam, a = 1819.2(9), b = 803.2(3), c = 367.6(2) pm, wR ² = 0.089, 893 F ² values and 36 parameters. The structure is an intergrowth variant of distorted trigonal and square prismatic slabs of compositions GdPt and GdIn. Together the platinum and indium atoms build up one-dimensional [Pt₂In₄] networks (292–333 pm Pt–In and 328–368 pm In–In) in an AA stacking sequence along the c axis. The gadolinium atoms fill distorted square and pentagonal prismatic cages between these networks with strong bonding to the platinum atoms.     

活性氮与SO2和SOCl2的传能反应

在流动余辉装置上, 研究了活性氮与SO2和SOCl2之间的反应过程. 在280～500 nm, 观察到了SO2( A1A2,B1B1→X1A1 )和SO2(a3B1→X1A1)的发射光谱. 对比由Ar(3P0,2)与N2碰撞反应产生的纯N2(A3Σu+)与SO2、SOCl2之间反应的实验结果, 可以说明, N2(A3Σu+)在活性氮与SO2的反应中是主要的能量载体, 它与SO2的直接能量转移反应形成了激发态的SO2(A1A2, B1B1); 在活性氮与SOCl2的反应中观测到的激发态SO2(a3B1), 则可能主要是通过N(4S)与SOCl2反应生成的N2O(X1Σ+)和N2(A3Σu+)与SOCl2反应生成的SO(X3Σ－)之间的化学反应过程产生.     

芳香化合物STM研究的进展

本文系统介绍了用STM技术研究苯、萘和蒽等芳香化合物的诸多成果，表明分子间相互作用、分子与基底间相互作用等对该类化合物吸附结构的影响，以及溶液中分子的结构、结构转化及表面反应与电极电位的关系，阐明了在原子分子惊讶上研究芳香化合物的重要性及发展趋势。     

Ionic Ozonides

Ionic Ozonides [1] were mentioned for the first time during the second half of the nineteenth century. However, fundamental aspects of their chemistry and physics remained obscure until more recently procedures had been provided that allow for their syntheses in gram‐amounts, and in high purity. Respective preparative approaches start by reacting the alkali metal superoxides KO₂, RbO₂, or CsO₂ with O₂/O₃ mixtures, at punctilious temperature control. Subsequently, the raw product is extracted with liquid ammonia. From the solution obtained, solid ozonides are harvested and purified by recrystallization. As rather versatile and efficient accesses to ozonides of further cations, metathesis reactions or cation exchange in liquid ammonia have been developed. The samples obtained have allowed for full structural and basic physical characterizations. All ionic ozonides known are metastable with respect to release of dioxygen, [NMe₄]O₃ being the most stable one (onset of rapid decomposition at 348 K). Depending on the respective crystal field, the bond lengths and angles of the ozonide anion vary significantly, and consistently, from 135 to 129 pm, and 113 to 120°, respectively. The magnetic moments of the paramagnetic O₃^? determined by susceptibility measurements (1.70–1.80 μ_B) deviate but slightly from the spin‐only value for one unpaired electron. This finding complies well with the small anisotropy of the g‐factors. As an achievement of possibly far reaching consequences, stable solutions of ionic ozonides in organic solvents have become available, opening the way to the use of O₃^? as a ligand, or synthon, in coordination and molecular chemistry.     

Thermodynamic Properties and Molecular Dipole Moments of Antimony Compounds from Quantum Chemical Evaluations

By the PM3 method, standard values of entropy, heats and Gibbs energies of formation and dipole moments of the molecules have been computed for a series of inorganic and organic antimony compounds. Linear dependences P exper = bP theor (where P is any of the mentioned properties) have been stated, allowing a priori evaluation of thermodynamic characteristics and molecular dipole moments of Sb-containing substances. It has been concluded that triphenylstibinedichloride in benzene solution, as well as triphenylstibinehydroxychloride in dioxane medium, exist in the form of trigonal bipyramid with two axial chlorine and oxygen atoms.     

Application of Phase Transfer Catalysis in Heterocyclic Synthesis: Synthesis of Some New Polyfunctional Thiophenes,Thiopyrans, Pyridines and Oxazines

The reaction of compound 1 with CS 2 and different active halo compounds gave the corresponding thiophene derivatives 2a,b-4a,b , whereas treatment of compound 1 with CS 2 and active methylene compounds afforded the corresponding thiopyran derivatives 5a,b , 6a,b , 7 , and 8 . Also, 1,3-thioxane derivatives 9 and 10 were obtained by reacting compound 1 with CS 2 and different cycloalkanones. Thiophene and pyrrolidene derivatives 11 , 12a,b , and 13a,b were obtained by reacting compound 1 with phenyl isothiocyanate and different halo compounds. The active methylene compounds and/or cycloalkanones were treated with compound 1 in the presence of phenyl isothiocyanate to give pyridines, thiopyran and oxazine derivatives 14a,b-16a,b , 17a-19a , and 19b , respectively.     

Low-Coordinated Organophosphorus Compounds

Low-coordinate organophosphorus compounds can be prepared by steric protection. They are diphosphenes, phosphaethenes, phosphaallenes, phosphabutatrienes, phosphaalkynes, and so on, of coordination number 2 and 1 .