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Synthesis of alkynes and alkynyl iodides bearing a protected amino alcohol moiety as functionalized amino acids precursors

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Science China Chemistry 2010年第9期53卷 1921-1926页

作者： AYED Charfedinne PICARD Julien LUBIN-GERMAIN Nadège UZIEL Jacques AUGE Jacques Université de Cergy-Pontoise Laboratoire de Synthèse Organique Sélective et Chimie bioOrganique-EA 4505

Amino acid precursors in protected amino alcohol form are important synthons that can be used as building-blocks for the hemisynthesis of non-natural amino *** can be used as a common starting material for the synthesis of such compounds differently ***,protected amino alcohols bearing an ethynyl and/or an iodoethynyl group can be used in cross-couplings,in 1,3-dipolar cycloadditions and/or in Nozaki-Hiyama-Kishi type *** thus demonstrated that the efficiently protected amino alcohols derived from serine can be coupled to a sugar derivative by an indium mediated alkynylation *** conditions of this coupling are compatible with such functionalized derivatives and allow envisaging an access to C-glycosylated amino acids.

关键词： amino alcohols amino acids oxazolidines alkynyl iodides C-glycoside indium alkynylation

Study of Divalent Rare Earth iodides

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Chinese Science Bulletin 1994年第5期39卷 407-410页

作者：王世华 Department of Chemistry Beijing Normal University Beijing 100875 PRC

Properties of trivalent rare earth ions have been extensively understood. Besidesthe +3 valent state, the rare earth elements also have +4, +2 and +1 valencies,clusters and mixture valent compounds. The research of their synthesis, structure,properties of unusual valent rare earth compounds has theoretical and practicalsignificance. It will broaden the horizon of rare earth chemistry and extend

关键词： divalent rare earth iodides synthesis structure properties measurement of valent state.

Study on gold concentrate leaching by iodine-iodide

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International Journal of Minerals,Metallurgy and Materials 2013年第4期20卷 323-328页

作者： Hai-xia Wang Chun-bao Sun Shao-ying Li Ping-feng Fu Yu-guo Song Liang Li Wen-qing Xie Key Laboratory of the Ministry of Education of China for High-Efficient Mining and Safety of Metal Mines University of Science and Technology Beijing China Gold Association Shuangqishan Gold Mine

Gold extraction by iodine-iodide solution is an effective and environment-friendly method. In this study, the method using iodine-iodide for gold leaching is proved feasible through thermodynamic calculation. At the same time, experiments on flotation gold concentrates were carried out and encouraging results were obtained. Through optimizing the technological conditions, the attained high gold leaching rate is more than 85%. The optimum process conditions at 25℃ are shown as follows： the initial iodine concentration is 1.0%, the iodine-to-iodide mole ratio is 1：8, the solution pH value is 7, the liquid-to-solid mass ratio is 4：1, the leaching time is 4 h, the stirring intensity is 200 r/mim, and the hydrogen peroxide consumption is 1%.

关键词： gold extraction leaching iodine iodides

A new non-electrolytic aluminum extraction method

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Transactions of Nonferrous Metals Society of China 2016年第9期26卷 2509-2517页

作者： Oleg G.PARFENOV Andrey D.KUSTOV Leonid A.SOLOVYOV Institute of Chemistry and Chemical Technology of SB RAS

A new method of primary aluminum extraction from alumina was proposed. The method is based on the new reaction AlI3＋（3/2）Zn=Al＋（3/2）ZnI2. In its turn, the exchange reaction AlCl3＋CaI2→AlI3＋CaCl2 is used to get aluminum iodide from aluminum chloride—the product of alumina carbochlorination. These reactions were studied in laboratory experiments as well as additional reactions, which were needed for the main chemicals recycling： Cl2, ZnI2→Zn, CaCl2→CaI2. XRD and SEM methods were used to investigate the phases and morphology of the reaction＇s solid products. The global free energy minimization method was used for the chemical equation＇s calculations. It was shown that aluminum can be effectively extracted from alumina without electrolysis, extreme high temperature and expended chemicals. The estimated specific carbon consumption and CO2 atmospheric pollution rate have to be halves of such values for the contemporary aluminum plant powered by the coal power station.

关键词： aluminum aluminum alloy chlorides iodides zinc iodine high-speed metallurgy

Crystal Structure of RbYbI_3

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Journal of Rare Earths 1997年第4期15卷 6-9页

作者：王梅天王世华

The crystal structure of RbYBI 3 is determined by X ray powder diffraction method, and its crystal structure is refined by Rietveld technique Its crystal structure is orthorhombic system with a =1 0383(3) nm, b =0 4667(1) nm, c =1 7200(5) nm The space group is Pnma (62), Z =4, and all of the atoms occupy the 4 c positions of the Pnma space group Each Yb atom is coordinated by six I atoms to form a distorted octahedron The main feature of the crystal structure of RbYbI 3 is two chains along the b axis which are composed of the edge sharing octahedra

关键词： Rare earths Rubidium iodides Rietveld technique Crystal structure