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Dr. Debabrata Mukherjee Prof. Dr. Jun Okuda 《Angewandte Chemie (International ed. in English)》2018,57(6):1458-1473
Solid magnesium hydride [MgH2]∞ has been pursued as a potential hydrogen‐storage material. Organic chemists were rather interested in soluble magnesium hydride reagents from mid‐20th century. It was only in the last two decades that molecular magnesium hydride chemistry received a major boost from organometallic chemists with a series of structurally well‐characterized examples that continues to build a whole new class of compounds. More than 40 such species have been isolated, ranging from mononuclear terminal hydrides to large hydride clusters with more than 10 magnesium atoms. They provide not only insights into the structure and bonding of Mg?H motifs, but also serve as models for hydrogen‐storage materials. Some of them are also recognized to participate in catalytic transformations, such as hydroelementation. Herein, an overview of these molecular magnesium hydrides is given, focusing on their synthesis and structural characterization. 相似文献
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Partial revision of the hydrated structure, and determination of the absolute configurations of geraniin and mallotusinic acid lead to structures I-A and II-A, respectively. 相似文献
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A simple method is presented for the determination of arsenic in rocks and in sediments by neutron activation. After irradiating
a sample it is, without any other treatment, directly heated in condensed phosphoric acid containing sodium chloride or sodium
bromide to evolve arsenic as arsenic(III) chloride or bromide. The distillate is absorbed in distilled water, in which arsenic
is later precipitated in elementary form by adding hypophosphite to the solution. From arsenite, arsenic(III) oxide, arsenate
and arsenic(III) sulphide, arsenic chloride can be evolved with NaCl-CPA reagent, but elementary arsenic and arsenic(V) oxide
do not react with it. However, metallic arsenic is found to react with KIO3-NaCl-CPA and arsenic(V) oxide with the NaBr-CPA, both both evolving arsenic(III) chloride or bromide. Therefore, successive
distillations, the first with NaCl-CPA and the second with NaBr-CPA, give a satisfactory means of differential determination
of arsenic(III) and arsenate as well as arsenic(V) oxide. For the elementary arsenic a problem still now remains. The chemical
recovery of carrier goes well beyond 95%.
Part of this work was performed at the Research Reactor Institute, Kyoto University. 相似文献
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Yasuhiro Okuda Yoshitomi Morizawa Koichiro Oshima Hitosi Nozaki 《Tetrahedron letters》1984,25(23):2483-2486
Whereas CuI catalyzed silylmagnesation of the tosylate of 5- hexyn-l-ol with the title reagent affords dimethylphenylsilylmethylenecyclopentane exclusively, the mesylate of 3-butyn-l-ol gives a mixture of unexpected silylcyclobutene and cyclopropylidene derivative. 相似文献
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Yutaka Saito Yukiko Inden-Okazaki Shoko Wada-Yano Atsuko Kanetsuna Kei-Ichi Miyazaki Masaki Mifune Yoshimasa Tanaka Hideki Okuda 《Analytica chimica acta》1985
A simple and sensitive method for assay of human serum albumin (5–80 μg) is based on binding of chrome azurol S by the albumin and determination of the bound dye spectrofluorimetrically. The method is sufficiently sensitive for application to spinal fluid (20–100 μl). 相似文献