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71.
Sokolov MN Gushchin AL Virovets AV Peresypkina EV Kozlova SG Fedin VP 《Inorganic chemistry》2004,43(25):7966-7968
Black single crystals of Ta(4)Se(9)I(8) are obtained in a high yield by heating Ta, Se, and I(2) at 300 degrees C in 1:2.2:1.0 molar ratio. In the structure, the tantalum atoms form a square, with four Se(2) ligands bridging the Ta-Ta edges and one capping the square. Each Ta atom has two terminal iodine atoms. The compound is diamagnetic and has only two electrons for metal-metal bonding. 相似文献
72.
Inclusion complexes of poly(ethylene oxide) with α-cyclodextrin are the key compounds in the synthesis of polyrotaxanes. These
complexes prepared in aqueous solutions contain free cyclodextrin, which cocrystallizes with the major reaction product. These
complexes dissociate upon dissolution in DMF and DMSO to form cyclodextrin and pseudopolyrotaxanes with a low cyclodextrin
content. Polyrotaxane was synthesized with the use of poly(ethylene oxide)-α,ω-bis-amine as a linear component. The end-groups
of the polymer in the inclusion complex were modified by the reaction with 2,4-dinitrofluorobenzene. A procedure was developed
for purification of a polyrotaxane with high cyclodextrin content.
__________
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1914–1918, August, 2005. 相似文献
73.
S. V. Trepalin A. V. Yarkov V. B. Sokolov A. N. Ivanov 《Russian Chemical Bulletin》1990,39(3):476-480
The potential function has been constructed for internal rotation of the NO-group in (CH3)2CClNO, CH3CCl2NO, and their deuterium analogs. It has been established that the N=O bond in the cisCl conformer of CH3CCl2NO does not eclipse the C-Cl bond, rather forming an angle of approximately 30. It has been shown that a change in substitutent on the -carbon atom may produce a substantial change in the form of the potential function of internal rotation (PFIR) of the NO group.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 550–555, March, 1990. 相似文献
74.
75.
Chelsea N. Widener Alexandria N. Bone Mykhaylo Ozerov Rachael Richardson 路正光 Komalavalli Thirunavukkuarasu Dmitry Smirnov 陈学太 薛子陵 《无机化学学报》2020,36(6):1149-1156
最近Ruamps和同事发现三角双锥构型的Ni(Ⅱ)配合物[Ni(Me6tren)Cl]ClO4(1,Me6tren=tris(2-(dimethylamino)ethyl)amine)具有大的单轴磁各向异性(J.Am.Chem.Soc.,2013,135:3017-3026)。他们利用HF-EPR研究获得横向零场分裂(ZFS)参数E=1.56(5)cm-1但未能确定轴向零场分裂参数D。在本工作中,我们利用0~17.5 T和5 K的变磁场远红外光谱(FIRMS)来检测自旋基态S=1中的MS=±1和MS=0态之间的磁跃迁。在FIRMS中直接观察到Zeeman分裂态之间的跃迁,得出轴向ZFS参数D=-110.7(3)cm-1。我们对1的晶体结构进行了Hirshfeld表面分析,揭示了1分子中的阳离子与阴离子之间以及分子之间的相互作用。 相似文献
76.
[structure: see text] An efficient total stepwise solid-phase synthesis of oligonucleotide-(3'-->N)-peptide conjugates is described that makes use of either a controlled pore glass support or macroporous polystyrene beads. Extending our previous homoserine linker approach, we prepared a range of conjugates containing one of four different cell or nuclear penetration peptides together with oligonucleotides containing 2'-deoxynucleoside or 2'-O-methylribonucleoside phosphodiesters, or gapmers containing 2'-deoxyphosphorothioates. The route also allows incorporation of a fluorescent label within the conjugate for cell uptake studies. 相似文献
77.
78.
Solodovnikov S. P. Tumanskii B. L. Bashilov V. V. Lebedkin S. F. Sokolov V. I. 《Russian Chemical Bulletin》2002,51(6):1009-1014
The ESR spectra of the products of oxidation of solutions and powders of Y@C82 and La@C82 with fuming sulfuric acid were studied. Based on the oxidation conditions and the sequence of spectral patterns, the spectra were attributed to the radical cations M@C82
n+ (n = 2, 4), dimers M3+
2@C164
+, and polyendometallofullerenes. 相似文献
79.
1-(2-Oxiranyl)-1,4-alkanediones were prepared from the ethylene acetals of ethyl 4-oxoalkanoates via the oxidation of the intermediate 1,2-dialkylcyclopropanols having a protected carbonyl group in an aliphatic chain. Intramolecular acetalization of these epoxy dicarbonyl compounds gave alkylated 6,8-dioxabicyclo[3.2.1]octan-2-ones in good yields. The latter were found suitable to be precursors for (±)-endo-brevicomin and its 2-hydroxy derivative, as well as (±)-endo-isobrevicomin and (±)-frontalin. 相似文献
80.