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Synthesis, spectroscopic, and X-ray structural characterization of Ru2HnCl4-nL4 (n = 2, 3) and Ru2H2F2L4 (L = PiPr3) are reported. The structure of Ru2HCl3L4 is also reported. These are dinuclear species containing two five-coordinate, approximately square-pyramidal metal atoms. Halides, not hydrides, preferentially occupy bridging sites, and the RuXL2 terminal moiety shows limited fluxionality, but hydrides do not migrate between metals. The limited steric protection provided by PiPr3 is evident from the dimerization observed and from the fact that all these structures have rather small [symbol: see text]P-Ru-P (approximately 105 degrees). Also reported are RuHXL2 species with X = acetylacetonate, phenoxide, O3SCH3, and O3SCF3. Several examples of coordinated olefin to complexed carbene conversions are used to test the influence of anion X on reactivity. 相似文献
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Polubarinova-Kochina's analytical differential equation methodis used to determine the pseudo-steady-state solution to problemsinvolving the freezing (solidification) of wedges of liquidwhich are initially at their fusion temperature. In particular,we consider four distinct problems for wedges which are: freezingwith the same constant boundary temperature, freezing with thesame constant boundary heat fluxes, freezing with distinct constantboundary temperatures and freezing with distinct constant fluxesat the boundaries. For the last two problems, a Heun's differentialequation with an unknown singularity is derived, which in bothcases admits a particularly elegant simple solution for thespecial case when the wedge angle is . The moving boundariesobtained are shown pictorially. 相似文献
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Srinu Bodige Parameshwar Ravula Kali Charan Gulipalli Srinivas Endoori Purna Koteswara Rao Cherukumalli Narendra Sharath Chandra JN 《合成通讯》2013,43(17):2219-2234
AbstractA novel series pyrrolo[3,2-b]pyridine-3-carboxamide linked 2-methoxypyridine derivatives have been designed, synthesized and confirmed by FT-IR, 1H NMR, 13C NMR, 19F NMR, MS, and elemental analysis. The synthesized compounds were screened for their antitubercular activity using microplate alamar blue assay method and antibacterial activity. Among the tested compounds, 4- fluorophenyl (8m), 4- chlorophenyl (8n) and 4-methoxyphenyl (8i) showed potent anti-TB activity (3.12?µg/mL) in comparison with reference drug, Pyrazinamide ((3.12?µg/mL). In addition, all compounds were docked into DprE1 (PDB code: 4KW5) to explore their binding interactions at the active site. The compounds exhibited essential key interactions as that of reported DprE1 inhibitors and hence, the synthesized compounds may be considered as molecular scaffolds for antitubercular activity. Compounds, 4-chlorophenyl (8n) and 4-flurophenyl (8m) showed significant antibacterial activity against Escherichia coli and Staphylococcus aureus strains. In silico prediction of toxicities, druglikeness and drug score profiles of the tested compounds are promising. 相似文献
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制备了五种对水稳定性好、带-SO3H官能团的磺酸类BrФnsted酸离子液体,用核磁共振(NMR)、红外光谱(IR)、电喷雾质谱(ESI-MS)、热重分析(TG)等表征手段对制备的离子液体进行了表征。结果表明,制备的离子液体与预期设计的结构一致,离子液体纯度大于95%;热重分析发现离子液体具有高的热稳定性和较宽的液态范围,其分解温度均高于300℃;五种离子液体均存在四种离子存在形式,H 可以单独以离子形式存在,并不是通常所认为的仅有两种离子存在形式。另外,研究了离子液体在常用溶剂中的溶解性,发现制备的离子液体易溶于水、甲醇,不溶于乙醚、甲苯和乙酸乙酯。 相似文献
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In the framework of relativistic harmonic confinement model for quarks and antiquarks, the masses of S- and P-wave mesons and pseudoscalar decay constants from light flavour to heavy flavour sectors are computed. The residual two-body
Coulomb interaction and the spin-dependent interaction of the confined one gluon exchange effects (COGEP) such as spin-spin
and spin-orbit interactions are perturbatively incorporated with the confinement energy to get the respective vector-pseudoscalar
meson mass differences. Here we employ the same parametrization and model parameters as used in a recent study of low-lying
hadron masses and leptonic decay widths. The results are being compared with the values obtained from other theoretical models
and the experimental values. 相似文献
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Reaction of [RuHClL2]2 (L = PiPr3) with 2-vinylpyridine gives L2ClRu(eta 2-CH=CHC5H4N) with liberation of H2. Reaction of [RuHClL2]2 with a range of olefins D(H)C=CR(EWG) substituted by electron-donating (D) and -withdrawing (EWG) groups occurs by oxidative addition of a vinyl C-H bond to give the metallacycles L2ClHnRu(eta 2-(++)C(D)=CR(EWG)). The 13C chemical shift of ++C and the fate of the "Hn" unit (decoordination, binding as H2, or binding as two hydrides) are strongly correlated, depend on the donating and withdrawing power of D and EWG, and can be used to decide whether ++C binds to Ru as a carbene or as a vinyl. These results emphasize the reducing power of Ru(II) when pi-acid ligands such as CO are absent. 相似文献