Ar原子电离能谱和Ar3p电子动量谱研究

电子动量谱学（ElectronMomentumSPectroscoP则是近．二十年来发展起来的一种新兴的探测原子、分子和固体结构的手段，它不仅能够获得轨道结合能的信息，而且能够能壳分辨地得到轨道电子的动量分布（即动量表象中的波函数模方）；同时它还是研究电子关联的最有效的实验手段．其     

Molecular Structure of 1,3,5-Tris (Trimethylstannyl) Benzene: An Electron Diffraction Study

The molecular structure of 1,3,5-tris (trimethylstannyl) benzene has been determined by gas-phase electron diffraction. The C — C bond length is in good agreement with that in benzene. In agreement with the somewhat electron-releasing character of the substituents, the endocyclic bond angles at the substituents are somewhat smaller than 120°. The mean value of Sn — C bond lengths is greater than that in tetraphenyltin and tetramethyltin. The SnMe₃ groups appear freely rotating around the C_aryl — Sn bonds. The following bond lengths (r _g) and bond angles were determined: (Sn — C)_mean 2.150 ± 0.007 Å, C — C 1.399 ± 0.005 Å, (C — H)_mean 1.105 ± 0.006 Å, < C — C(Sn) — C 117.7 ± 1.7º, < C_aryl — Sn — C_methyl 106.7 ± 0.7º < Sn — C — H 111.5 ± 0.9º.     

Synthesis and anticonvulsant activity of new fluorinated N-phenyl- and N-benzyl-2-azaspiro[4.4]nonane- and [4.5]decane-1,3-dione derivatives: Part III

A series of N-phenyl- and N-benzyl-2-azaspiro[4.4]nonane- and [4.5]decane-1,3-diones containing a fluoro or trifluoromethyl substituents at the aryl ring was synthesized and tested for their anticonvulsant activity in the maximal electroshock (MES) and subcutaneous metrazole (sc.Met) tests. Among them, the most active were N-benzyl derivatives with fluoro and trifluoromethyl substituents especially at position-2 of the aryl moiety. The introduction of the phenyl ring at the imide nitrogen atom resulted in less active compounds. The results obtained showed that incorporation of fluoro or trifluoromethyl substituents increased the anticonvulsant activity in comparison to respective chloro, methoxy or methyl analogues. Crystallographically obtained conformation for one active and two inactive derivatives with trifluoromethyl substituents at position-2 or -3 of phenyl ring were initially used for molecular electrostatic potentials (MEP) calculation. The MEP distribution at carbonyl oxygen atoms was different for active and inactive molecules.     

The effect of (natural) polyols on the initial colour of heavy metal- and zinc-free poly(vinyl chloride)

The propensity of (natural) polyols dispersed in heavy metal- and zinc-free PVC sheets to improve the initial colour, e.g. the colour during the first minutes of exposure to high processing temperatures (short-term stability), has been investigated. It is shown using W(Lab) values that the initial colour improves upon addition of polyols containing primary hydroxyl groups. The polyols act as HCl scavengers, presumably via an acid-catalysed S_N2 substitution of the primary hydroxyl groups by chloride ions. In contrast, polyols with only secondary or tertiary hydroxyl groups accelerate the thermal degradation of PVC. Notwithstanding, the efficacy of the (natural) polyols containing primary hydroxyl groups will be reduced if the polyol is susceptible to competitive acid-catalysed intramolecular cyclodehydration reactions under the processing conditions. This is substantiated by a comparison of the behaviour of mannitol and 3,4-di-O-methyl-d-mannitol. The methylated derivative, which is less prone to undergo intramolecular cyclodehydration, improves the initial colour of heavy metal- and zinc-free PVC sheets more significantly than mannitol itself.     

Flavonoids of <Emphasis Type="Italic">Scutellaria immaculata</Emphasis> Roots

(±)-5,2′-Dihydroxy-6,7,6′-trimethoxyflavanone, (-)-5,2′-dihydroxy-6,7,8,6′-tetramethoxyflavanone, chrysin, wogonin, apigenin, isoscutellarein, scutellarein, cosmosiin, and the new flavonoid wogonin-7-O-β-D-glucopyranoside, the structure of which was established using chemical transformations and spectral data, were isolated from Scutellaria immaculata roots.__________Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 26–28, January–February, 2005.     

Highly tilted antiferroelectric (R) enantiomers useful for the formulation of eutectic mixtures

ABSTRACT

Novel chiral three-ring (R) enantiomers were synthesised using optically active (R)-(?)-2-octanol. Properties, such as the sequence of phases, the transition temperatures and enthalpies, were tested by a polarising optical microscope and differential scanning calorimeter. An antiferroelectric smectic phase (SmC_A*) with a direct transition from the antiferroelectric to the isotropic phase (SmC_A*-Iso) was observed for three esters with an achiral C₃F₇CH₂O(CH₂)₃O– terminal chain. Bi- and multicomponent mixtures with a broad temperature range of the antiferroelectric phase and good electro-optical properties were formulated. Helical pitch of pure esters and mixtures was measured by spectrophotometry method.     

Zinc(II) (o-hydroxybenzaldoximates) Complexes with Mono- and Bidentate Ligands

New complexes:Zn(Hsalox)(ox), Zn(Hsalox)(NHPh), Zn(Hsalox)(Hsal) and Zn(Hsalox)₂(1,2-diMeim) have been synthesised as a result of a reaction of Zn(salox) and Zn(Hsalox)₂ (where: salox ^2–=OC₆H₄CHNO^2–, Hsalox ^–=OC₆H₄CHNOH^–) with 8-hydroxyquinoline (Hox), o-aminophenol (NH₂Ph), o-hydroxybenzoic acid (H₂Sal) and 1,2-dimethylimidazole (1,2-diMeim). Chemical, X-ray and thermal analyses of the complexes and their sinters have been carried out. Thermal decomposition pathways have been postulated for the complexes. The mixtures about not definite composition have been obtained as a result of a reaction of zinc(o-hydroxybenzaldoximates) with imidazole(Him) and 4-methylimidazole (4-MeHim). This revised version was published online in August 2006 with corrections to the Cover Date.     

N, N'-二取代二硫代草酰胺与二元胺反应的研究

本文研究了N, N'-二取代二硫代草酰胺与二元胺(乙二胺、1, 3-丙二胺、反-1,2-环己二胺)在二甲基亚矾中的反应。用IR、^1H NMR和四圆衍射法测定了产物的结构。实验结果表明, 反应存在着两种方式, 一种是二元胺的两个氨基反应在同一个硫代酰基的碳原子上(如乙二胺、1, 3-丙二胺)。而另一种由于立体的影响,反应在两个相邻硫代酰基的两个碳原子上(如反-1, 2-环己二胺)。     

Zur Synthese von fungizid wirksamen Isocamphanderivaten: Synthesen in der Isocamphanreihe, 34. Mitt.

Summary Some esters of isocamphenilanic acid (4) have been prepared and tested for their fungicidal and insecticidal activity. Esters of various acids with isocamphanyl ethylalcohol (5) have also been synthesized and included in the fungicidal/acaricidal/insecticidal screening programme. All esters bear a geminal dimethyl group at C-3 of the bicyclus which is important because of its shielding effect.

     

Synthesis of Sulfur-Containing Bis-Terpenoids Based on Monoterpene Oxides

Ethanedithiol and di(mercaptoethyl)sulfide react regio- and stereoselectively with (+)-3-carene and -hydroxy(-)--pinene -oxides in the presence of sodium ethoxide to give the corresponding bis- and tris-sulfides with two terpene fragments