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A method has been developed for the obtaining of new oligo(dimethyl)silanes comprising 1,7-bis(methyl)-m-carboranyl units and bearing the terminal chlorosilyl or methoxysilyl groups. Reactions of such oligomers with an excess of benzylmagnesium chloride or 1-chloromagnesiummethyl-m-carborane lead to oligo-m-carboranylenemethylenesilanes containing the terminal benzylsilyl or m-carboranylmethylenesilyl groups. The novel oligomers are highly viscous liquids possessing a high heat resistance and also a resistance towards the treatment with a strong alkaline reagent.

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(Perfluoroalkyl)phenyliodonium sulfonates underwent novel oxy-perfluoroalkylation with alkenes under oxygen atmosphere in the presence of a base.  相似文献   

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A photoresponsive rotaxane based on the photoheterolysis of an acridane unit which is at the same time a bulky end group has been developed.  相似文献   

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Novel heterocyclic organoboranes are obtained from the interaction of an organic isocyanate and heterocyclic aminoboranes  相似文献   

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The preparation of silicon nanotubes is a subject of great importance for both the theoretical and experimental work in the nanotube research field since it could lead to a wealth of new physics and chemistry because of the unique properties of silicon as compared with its carbon analogue. Some structures of nanoscale silicon and silicon composites, such as silicon nanowire1, silicon nano-clusters2 and SiC nanorods3 have been discovered and investigated. The silicon nanotubes, however, have …  相似文献   

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A novel cyclobutane‐type norlignan, peperotetraphin (=methyl rel‐(1R,2S,3S)‐2,3‐bis(7‐methoxy‐1,3‐benzodioxol‐5‐yl)cyclobutanecarboxylate; 1 ), and a novel phenylpropanoid, i.e., methyl (2E)‐3‐(7‐methoxy‐1,3‐benzodioxol‐5‐yl)prop‐2‐enoate ( 2 ), along with three known compounds, α‐asarone (=1,2,4‐trimethoxy‐5‐[(1E)‐prop‐1‐en‐1‐yl]benzene), vanillic acid (=4‐hydroxy‐3‐methoxybenzoic acid), and veratric acid (=3,4‐dimethoxybenzoic acid), were isolated from the EtOH extract of the whole plant of Peperomia tetraphylla. Their structures were determined by spectroscopic methods, especially 1D‐ and 2D‐NMR techniques. This is the first report of naturally occurring cyclobutane‐type norlignans.  相似文献   

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The structure of organosilicon betaines R3P+CMe2SiMe2S (R = Ph and Me2N) was determined by X-ray diffraction analysis.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 339–340, February, 1994.  相似文献   

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由于结构中特殊的四面体层,使得"114"化合物在磁性和存储氧性质方面有潜在的应用价值。本文以传统的高温固相法合成新型化合物YBaZn_3GaO_7,在其八面体位掺杂有效半径更小的Sc~(3+),得到全固熔化合物Y_(1-x)Sc_xBaZn_3GaO_7(x=0~1)。结构精修确定此系列"114"化合物空间群为P6_3mc。解析其结构后发现,随着掺杂量的增多结构有明显的演变趋势。从YBaZn_3GaO_7到ScBaZn_3GaO_7晶胞参数线性减小,通过对各配位元素键长的分析,说明随着掺杂量增加,结构畸变减小,应力减小,四面体配位中的Zn~(2+)和Ga~(3+)得到整合,从而得到结构更加稳定的"114"化合物。  相似文献   

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Two copper-complex-substituted tungstogermanates [Cu5(2,2'-bpy)6(H2O)][GeW8O31].9H2O, 1, and {[Cu5(2,2'-bpy)5(H2O)][GeW9O34]}2.7H2O, 2 (2,2'-bpy = 2,2'-bipyridyl), have been hydrothermally synthesized and structurally characterized. X-ray structural analyses show that 1 is a rare tetralacunary Keggin anion of [B-beta-GeW8O31]10- substituted by copper complexes, while dimer 2 consists of two trilacunary [B-alpha-GeW9O34]10- Keggin units bridged by copper complexes. Magnetic measurement for 2 shows the presence of antiferromagnetic interactions within the dinuclear Cu2+ cations.  相似文献   

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Methods are reported for preparing the novel pyrimidines 7,8-dihydro-9H-1,2,5-chalcodiazolo[3,4-d]thiazole[2,3-b]pyrimidin-4-ones and their N-oxides.A. V. Bogatskii Physicochemical Institute, National Academy of Sciences of Ukraine, Odessa, 270080. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1130–1132, August, 1998.  相似文献   

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Gallium(III)(pyridine) complex of 5,10,15-tris(pentafluorophenyl)corrole-3-carbaldehyde was used as a precursor of an azomethine ylide, which was trapped in 1,3-dipolar cycloaddition reactions with quinones. Besides the expected dehydrogenated 1,3-dipolar cycloadducts, novel quinone-fused corrole derivatives were also obtained in moderate yields.  相似文献   

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Novel 1,7-dihydro- or 1,2,6,7-tetrahydronaphthalene derivatives were obtained from naphthalene through a polysilylation/oxidation process as well as 1,4,6,7-tetrakis(trimethylsily)naphthalene, a regiospecific precursor of 1,4,6,7-tetrafunctional naphthalenes.  相似文献   

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In this work we report a new type of pH-responsive micelle-like nanoparticle. Reversible nanoscale structures are formed in solutions of a pH-sensitive hydrophobic polyelectrolyte, poly( N-methacryloyl- l-valine) or poly( N-methacryloyl- l-phenylalanine), and nonionic surfactant (Brij 98) in the presence of hydrochloric acid. The influence of composition and pH on particles size and shape was investigated by a variety of methods. An entity's size and polydispersity could be varied in a broad range making them a perspective candidate as a drug carrier. Unlike the case of typical micelles, our results indicate the presence of cavities in the formed particles. A hypothetical model of a nanoparticle and mechanism of formation are proposed.  相似文献   

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