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111.
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113.
The use of a combination of IrCl3 with a series of ligands derived from the C2-symmetric diamine diphenylethanediamine (DPEN) forms a catalyst capable of the asymmetric hydrogenation of ketones in up to 85% ee. 相似文献
114.
Hopewell JP Martins JE Johnson TC Godfrey J Wills M 《Organic & biomolecular chemistry》2012,10(1):134-145
The preparation of a range of asymmetric iron and ruthenium-cyclone complexes, and their application to the asymmetric reduction of a ketone, are described. The enantioselectivity of ketone reduction is influenced by a single chiral centre in the catalyst, as well as by the planar chirality in the catalyst. This represents the first example of asymmetric ketone reduction using an iron cyclone catalyst. 相似文献
115.
Matharu DS Morris DJ Clarkson GJ Wills M 《Chemical communications (Cambridge, England)》2006,(30):3232-3234
A Rh/tetramethylcyclopentadienyl complex containing a tethered functionality has been demonstrated to give excellent results in the asymmetric transfer hydrogenation of ketones in both aqueous and formic acid/triethylamine media. 相似文献
116.
The attachment of a tethering group from the basic nitrogen atom to the arene ligand of a ruthenium(II) catalyst greatly improves its ability to catalyze asymmetric transfer hydrogenation (ATH) reactions. In this paper, we describe further applications of this versatile system to an extended substrate range. 相似文献
117.
Jrg M. Wills 《European Journal of Combinatorics》2008,29(8):1952
We construct a polyhedral 2-manifold of genus 2 embedded in Euclidean 3-space, and hence oriented, built up of 12 planar (but nonconvex) heptagons, three meeting at each vertex, i.e., locally regular or equivelar. The polyhedron is face-minimal among all equivelar polyhedra of genus g≥2.It has a threefold symmetry axis and exists in two chiral versions. 相似文献
118.
Canted ferromagnets present a important class of molecular magnets. In these materials the uncompensated magnetisation, created by the DzyaloshinskyMoriya interaction, has the particular property of being compatible with the symmetry of the underlying antiferromagnetic Hamiltonian. If the ordering transition is continuous, Landau theory and simple symmetry arguments about the crystal structure can be used to determine whether such parasitic ferromagnetism is possible, and therefore to aid the systematic search for new molecular ferromagnets. 相似文献
119.
The asymmetric transfer hydrogenation of a series of 2,2-dimethyl-6-(2-oxoalkyl)-1,3-dioxin-4-ones and 2,2-dimethyl-6-(2-oxoaryl)-1,3-dioxin-4-ones was achieved in high enantiomeric excess using a Ru(II) catalyst. The aryl substrates were most compatible with the methodology and this process facilitated a total synthesis of enantiomerically pure (+)-yashabushitriol. 相似文献
120.
Yulin Qi Huilin Li Rebecca H. Wills Pilar Perez-Hurtado Xiang Yu David P. A. Kilgour Mark P. Barrow Cheng Lin Peter B. O’Connor 《Journal of the American Society for Mass Spectrometry》2013,24(6):828-834
The method of phasing broadband Fourier transform ion cyclotron resonance (FT-ICR) spectra allows plotting the spectra in the absorption-mode; this new approach significantly improves the quality of the data at no extra cost. Herein, an internal calibration method for calculating the phase function has been developed and successfully applied to the top-down spectra of modified proteins, where the peak intensities vary by 100×. The result shows that the use of absorption-mode spectra allows more peaks to be discerned within the recorded data, and this can reveal much greater information about the protein and modifications under investigation. In addition, noise and harmonic peaks can be assigned immediately in the absorption-mode. Figure
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