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71.
The synthesis of (?)-N-Cyanomethyl-4-phenyl-1,3-oxazolidine 1 is reported. Good yields and moderate diastereomeric excesses (d.e.s.) of mono- and di-substituted α-aminonitriles were obtained from this simple chiral template.  相似文献   
72.
Catalytic asymmetric hydroboration can be successfully applied to meso bicyclic hydrazines. The resulting alcohols are of great synthetic interest and can lead in a straightforward manner to cyclopentanic diamino alcohols with good enantiomeric purity.  相似文献   
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NH3 and PH3 rotation and rotation-inversion line parameters in the far to medium i.r. are calculated for remote sounding purposes of planetary atmospheres; 1607 lines of 14NH3, 362 lines of 15NH3 and 325 lines of PH3 are compiled. The absolute intensity formulation has been reviewed in the case of rotation adn rotation-inversion lines of molecules with C3v symmetry. The justification of the general agreement between the authors, and comparisons with other published expressions are given.  相似文献   
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A simple and versatile method for the enantio- and diastereoselective synthesis of mono- or disubstituted 3-aminoazepanes is described. The key step involves a highly regio- and diastereoselective tandem ring-enlargement/alkylation or reduction process. This novel synthetic route provides enantiomerically pure constrained diamines interesting as scaffolds for medicinal chemistry.  相似文献   
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In the present paper a study of the liquid phase behavior in aqueous systems of imidazolium-based ionic liquids (ILs) with the bis{(trifluoromethyl)sulfonyl}imide anion is addressed. To highlight the influence of the C5 alkyl side group structure on their properties, a series of ILs with linear, branched, and cyclic substituents was studied. As was already shown in our previous work, very subtle changes in the cation structure at the molecular scale can have a significant and unexpected impact on the bulk properties. Therefore, in this work, the mutual solubilities of 1-butyl-3-alkylimidazolium bis{(trifluoromethyl)sulfonyl}imide ionic liquids and water were studied, both experimentally and by modeling, at atmospheric pressure as a function of temperature from 293.15 to 328.15 K. The solubilities of the ionic liquids in water are very low, typically around 10?5 mole fraction units and were measured by a direct analytical method, making use of UV–Vis spectrophotometry. The solubilities of water in the ionic liquids were found to be around 0.20 mole fraction units and were measured using the cloud-point method. In addition to the experimental data, the liquid–liquid equilibria in the systems were modeled using the COSMO-RS methodology. Phase diagrams and the critical solution points were also estimated by applying the universal scaling laws based on the 3D Ising model, taking into account the non-linearity of the diameter and crossover to mean-field behavior.  相似文献   
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