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Synergistic extraction of rare earth by mixtures of 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester and di-(2-ethylhexyl) phosphoric acid from sulfuric acid medium 被引量:9
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作者 黄小卫 李建宁 +3 位作者 龙志奇 张永奇 薛向欣 朱兆武 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第3期410-413,共4页
The extraction of Nd^3+ and Sm^3+, including the extraction and stripping capability as well as the separation effect of Nd^3+ or Sm^3+, from a sulfuric acid medium, by mixtures of di-(2-ethylhexyl) phosphoric a... The extraction of Nd^3+ and Sm^3+, including the extraction and stripping capability as well as the separation effect of Nd^3+ or Sm^3+, from a sulfuric acid medium, by mixtures of di-(2-ethylhexyl) phosphoric acid (HDEHP, H2A2(0)) and 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester (HEH/EHP, H2L2(0)) were studied. The distribution ratios and synergistic coefficients of Nd^3+ and Sm^3+ in different acidities were also determined. A synergistic extractive effect was found when HDEHP and HEH/EHP were used as mixed extractants for Sm^3+ or Nd^3+. The chemical compositions of the extracted complex were determined as Nd.(HA2)2-HL2 and Sm.(HA2)2-HL2. The extraction equilibrium constants, enthalpy change, and entropy change of the extraction reaction were also determined. 展开更多
关键词 di-(2-ethylhexyl) phosphoric acid 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester synergistic extraction mechanism Sm^3+ Nd^3+ rare earths
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Enantioselective trapping of oxonium ylide intermediates by N-benzhydryl-α-imino ester:Synthesis of β-tetrasubstituted α-amino acids
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作者 Shi-Kun Jia Yu-Bing Lei +2 位作者 Long-Long Song Shun-Ying Liu Wen-Hao Hu 《Chinese Chemical Letters》 SCIE CAS CSCD 2017年第2期213-217,共5页
A synergistic rhodium(Ⅱ)/phosphoric acid catalyzed three component reaction of 3-diazooxindoles,alcohols and N-benzhydryl-α-imino ester is developed for the efficient construction of chiral β-alkoxy C-β-tetrasub... A synergistic rhodium(Ⅱ)/phosphoric acid catalyzed three component reaction of 3-diazooxindoles,alcohols and N-benzhydryl-α-imino ester is developed for the efficient construction of chiral β-alkoxy C-β-tetrasubstituted α-amino acid derivatives in good yields and with excellent diastereoselectivities and high enantioselectivities.The synthetic application of the resulting products was illustrated by reducing with Pd/C under H_2 atmosphere followed reacting with CSCl_2 at room temperature to rapid afford 3-spirocyclic oxindole in a good yield with a chirality retainment.The three-component reaction is proposed to proceed through an electrophilic trapping of the oxonium ylides by N-benzhydryl-α-imino ester. 展开更多
关键词 Three-component reaction Oxonium ylide N-Benzhydryl-α-imino ester β-Tetrasubstituted α-amino acids Chiral phosphoric acid
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