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971.
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A new synthesis of γ,δ-unsaturated quaternary α-amino acid derivatives was developed utilizing N-alkylation and Claisen rearrangement of allyl α-iminocarboxylates. 相似文献
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The application of layered solids for molecular recognition is summarized. By using layered solids (silicates, aluminosilicates, titanates, hydroxides, and so on), ions and molecules can be concentrated from aqueous and vapor phases. The large surface area and tunable surface properties derived from the layered structures contribute to molecular recognition. The choice of materials and modification of the nanostructure were carefully investigated to optimize the performance based on molecular recognition (selective adsorption, substrate selective reaction, detection, etc.). The progress made in materials syntheses (variation of layered materials, sophisticated modification, controlled morphology, and processing) has made the design of materials more attractive and realistic. 相似文献
976.
A novel and facile one-pot isomerization of aldo-disaccharides to keto-disaccharides is achieved by making use of deep sea water in sub-critical conditions. The resulting keto-disaccharides having pharmaceutical and food applications were obtained in modest yields of about 30–32% at the optimum reaction conditions (temperature: 180 °C, reaction time: 5 min). Detailed investigation of all major ions in deep sea water revealed that bicarbonate ions play a key role as a catalyst in this isomerization reaction. 相似文献
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Yoshihisa Kakuta Naoyuki Masuda Michihiro Kurushima Takashi Hashimoto Daisuke Yoshioka Hiroshi Sakiyama Yuya Hiraoka Makoto Handa Masahiro Mikuriya 《Chemical Papers》2014,68(7):923-931
The template reaction of salicylaldehyde and its substituted derivatives and 2-hydroxy-5-bromobenzylamine or 2-hydroxy-5-chlorobenzylamine with copper(II) acetate in dimethyl sulphoxide (dmso) afforded eight dinuclear Cu(II) complexes, [Cu2(L)2(dmso)2] (H2 L = N-salicylidene-2-hydroxy-5-bromobenzylamine, N-salicylidene-2-hydroxy-5-chlorobenzylamine and their 5-bromo, 5-nitro and 5-methyl-substituted salicylidene derivatives). These Cu(II) complexes were characterised by IR and UV-VIS-NIR spectroscopy, electric conductivity, cyclic voltammetry, and temperature dependence of magnetic susceptibilities (4.5–300 K). In the THF solution, the complexes are nonelectrolytes and exhibit a characteristic CT band due to phenoxido-bridging at 360–384 nm. In the cyclic voltammograms, an irreversible reduction process was observed at ?1.18–1.54 V vs Fc/Fc+. Single-crystal X-ray crystallography revealed that two Cu(II) ions were bridged by the two phenoxido-oxygen atoms of the two Schiff-base ligands with axial coordination of dmso molecules forming a square pyramid with a Cu-Cu distance of 3.0628(8)–3.0931(6) °A. In accordance with the crystal structures, the magnetic interaction between the two Cu(II) ions is relatively anti-ferromagnetic with ?2J value of 386–575 cm?1. The axial coordination effect of the dmso molecule was discussed in relation to the correlation between the Cu-O-Cu angle and the ?2J value. 相似文献
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