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Copper-Catalyzed C-C(O)C Bond Cleavage of Monoalkylated β-Diketone: Synthesis of α,β-Unsaturated Ketones
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作者 Tony Wheellyam Pouambeka Victor N’goka +3 位作者 Narcisse Nicaise Obaya Guy Crépin Enoua Hubert Makomo Qian Zhan 《International Journal of Organic Chemistry》 2023年第2期41-49,共9页
A new and simple route for the synthesis of α,β-unsaturated ketones via cleavage of the C-C(O)C single bond of monoalkylated β-diketone has been described. The reaction was catalyzed by copper, a cheap transition m... A new and simple route for the synthesis of α,β-unsaturated ketones via cleavage of the C-C(O)C single bond of monoalkylated β-diketone has been described. The reaction was catalyzed by copper, a cheap transition metal in a weakly basic medium (K<sub>3</sub>PO<sub>4</sub>) at room temperature. To carry out this study, we first had to synthesize the monoalkylated β-diketones 1. Afterwards, α,β-unsaturated ketones 2 were obtained with high yields around 80%. Finally, all the products were characterized by 1H NMR, 13C NMR, and HRMS spectra. . 展开更多
关键词 monoalkylated β-diketone α β-Unsaturated Ketones COPPER-CATALYZED C-C(O)C Bond Cleavage
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Monoalkyl Esters of Isoalkylphosphonic Acid as Extractants in Rare Earth Separation
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作者 陈德朴 钟攸兰 梁树权 《Journal of Rare Earths》 SCIE EI CAS CSCD 1992年第2期142-147,共6页
Four monoalkyl esters of isoalkylphosphonic acids have been studied for the chromatographic separation of rare earths (RE).The relationship between distribution ratios and acid concentration of the eluants for samariu... Four monoalkyl esters of isoalkylphosphonic acids have been studied for the chromatographic separation of rare earths (RE).The relationship between distribution ratios and acid concentration of the eluants for samarium and ytterbium has been explored.The characteristics of these extractants loaded onto macroreticular poly (methyl methacrylate) resin beads for the separation of lanthanum,cerium,praseodymium and neodymium have been compared.Among the extractants studied,mono(1-methylheptyl) ester of isooctylphosphonic acid was found to be the best for RE separation.The acidity for separation is lower than any known P-containing extractants for the same purpose.For instance,with 1.73 mol·L^(-1) nitric acid as eluent,thulium,ytterbium and lutetium can be separated quantitatively.The extractant-loaded resins possess high column efficiency with good kinetic characteristics.The extraction mechanism was also explored. 展开更多
关键词 Rare earth separation Monoalkyl isoalkylphosphonates Extractant-loaded resins Extraction mechanism
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Synthesis of 1,3-cyclic Monoalkyl(acyl)-racglycerothiophosphates of Uridine
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作者 Cheng Xiang ZHANG Ru Yu CHEN +1 位作者 Chu Chi TANG Huan Ming CHEN(Research Institute of Elemento Organic Chemistry Key Laboratory of Elemento Organic Chemistry Nankai University, Tianjin, 300071) 《Chinese Chemical Letters》 SCIE CAS CSCD 1996年第10期894-895,共2页
New structural phospholipids 1.3-cyclic monoalkyl(acyl)-rac-glycerothiophosphates of uridine were synthesized. The strategy for the synthesis is using hexaethylphosphorous triamide, activated by a catalytic amount of ... New structural phospholipids 1.3-cyclic monoalkyl(acyl)-rac-glycerothiophosphates of uridine were synthesized. The strategy for the synthesis is using hexaethylphosphorous triamide, activated by a catalytic amount of iodine, as the phosphorylating reagent. Their structures were confirmed by (1)HNMR, (31)PNMR, IR and elemental analysis. 展开更多
关键词 Synthesis of 1 3-cyclic Monoalkyl ACYL
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