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81.
The novel thiophenolato hydrido iron(II) complexes [cis-Fe(H)(SAr)(PMe3)4] (4–6) (Ar = p-BrC6H4 (4), p-MeOC6H4 (5) and o-MeC6H4 (6)) were prepared through the reaction of Fe(PMe3)4 with thiophenols ArSH (1–3). Reaction of 6 with trimethylsilylacetylene and phenylacetylene afforded bisalkynyl iron(II) complexes [Fe(PMe3)4(CCSiMe3)2] (7) and [Fe(PMe3)4(CCPh)2] (9) through elimination of dihydrogen and the formation of thiophenol. The reaction of 5 with 2-methyl-3-butyn-2-ol gave [Fe(PMe3)4(CCCMe2OH)2] (10). The crystal structures of complexes 4, 7 and 10 were determined by X-ray diffraction. A mechanism for the formation of 7 is proposed. 相似文献
82.
Alex R. Petrov Konstantin A. Rufanov Klaus Harms Jörg Sundermeyer 《Journal of organometallic chemistry》2009,694(7-8):1212-1218
The influence of the ether ligand in [LnCl3(solv)n], solv = THF, DME; n = 1–3 in reactions with ortho-lithiated dimethyl-benzylamine Li(dmba) has been studied. An improved protocol towards homoleptic tris-aryl complexes of the type [Ln(dmba)3], Ln = Y, Er and Yb has been developed and molecular structures of these complexes have been established by X-ray crystallography. For the first time stable homoleptic lithium ate-complexes of the type Li[Ln(dmba)4] (Ln = Gd, Nd) have been isolated and structurally characterized. The success in their synthesis strongly depends on the choice of the appropriate [LnCl3(solv)n] precursor, such as [GdCl3(dme)2], [NdCl3(dme)], and THF-free reaction conditions. Factors influencing on possible degradation pathways of lanthanide tris-aryl complexes with dmba-type ligands are discussed. 相似文献
83.
Mike Friedrich Revaz Nozadze Sandra de Keijzer Ralf Steinmeyer Vladimir Ermolayev Gregory S. Harms 《Journal of fluorescence》2018,28(1):29-39
Single molecule detection and tracking provides at times the only possible method to observe the interactions of low numbers of biomolecules, inlcuding DNA, receptors and signal mediating proteins in living systems. However, most existing imaging methods do not enable both high sensitivity and non-invasive imaging of large specimens. In this study we report a new setup for selective plane illumination microscopy (SPIM), which enables fast imaging and single molecule tracking with the resolution of confocal microscopy and the optical penetration beyond 300 μm. We detect and report our instrumental figures of merit, control values of fluorescence properties of single nano crystals in comparison to both standard widefield configurations, and also values of nanocrystals in multicellular “fruiting bodies” of Dictyostelium, an excellent control as a model developmental system. In the Dictyostelium , we also report some of our first tracking of single nanocrystals with SPIM. The new SPIM setup represents a new technique, which enables fast single molecule imaging and tracking in living systems. 相似文献
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A Mukherjee M Dasgupta DJ Hinde CR Morton AC Berriman RD Butt JO Newton H Timmers 《Pramana》2001,57(1):195-198
Fusion cross-sections for the 7Li + 12C reaction have been measured at energies above the Coulomb barrier by the direct detection of evaporation residues. The heavy
evaporation residues with energies below 3 MeV could not be separated out from the α-particles in the spectrum and hence their
contribution was estimated using statistical model calculations. The present work indicates that suppression of fusion cross-sections
due to the breakup of 7Li may not be significant for 7Li + 12C reaction at energies around the barrier. 相似文献
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