排序方式: 共有582条查询结果,搜索用时 15 毫秒
581.
Annette E. Buba Author VitaeAuthor Vitae Lukas J. Gooßen Author Vitae 《Journal of organometallic chemistry》2011,696(1):170-7449
A catalyst system formed in situ from bis(2-methallyl)cycloocta-1,5-diene-ruthenium(II) [(cod)Ru(met)2], 1,4-bis(dicyclohexylphosphino)butane (dcypb) and ytterbium(III) triflate hydrate (Yb(OTf)3) was found to catalyze the addition of nitrogen nucleophiles to terminal alkynes under mild conditions to stereoselectively form the Z-enamide or Z-enimide products. Various secondary amides and imides could be added across the triple bond of a range of aliphatic and aromatic alkynes. The new bimetallic catalyst system sets new standards with regard to scope and selectivity for the synthesis of Z-configured anti-Markovnikov enamides. 相似文献
582.
Ruiren Tang Author Vitae Chunhua Tang Author VitaeAuthor Vitae 《Journal of organometallic chemistry》2011,696(10):2040-306
A novel polyamino polycarboxylic pyridine derivative ligand, N,N,N1,N1-(2,6-bis((3-(aminoethyl)-5-methyl-1H-pyrazol-1-yl)methyl)pyridine)hexakis(acetic acid) (L), was designed and synthesized with the motive that it is able to sensitize the emission of lanthanides. Its corresponding Eu(III) and Tb(III) complexes Na4EuLCl3·3H2O and Na4TbLCl3·5H2O were successfully prepared. The ligand and the complexes were characterized by elemental analysis, IR, MS, NMR and TG-DTA. The luminescence properties of the compounds in solid state were investigated; each complex had very narrow emission bands and strong luminescence intensity up to about 10,000. The TG-DTA studies showed that the initial decomposition temperature of both complexes was over 250 °C, elucidating the complexes had a high thermal stability. Meanwhile, the comparison with similar complexes suggested that the ligand with more coordination sites possessed more efficient antenna effect. To explore the potential medicinal value of L, the binding interaction of L and bovine serum albumin (BSA) was carried out by fluorescence spectrum. The studies indicated that the reaction between L and BSA was a static quenching procedure. The binding site number n and binding constant Ka were calculated according to the double logarithm regression equation. The thermodynamic parameters showed the Van der Waals and hydrogen bond interactions were the mainly impulse to the reaction. 相似文献