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Patrick Bösing Beate Neumann Hans‐Georg Stammler Norbert W. Mitzel Prof. Dr. 《无机化学与普通化学杂志》2009,635(15):2388-2390
The reaction of HON(tBu)CH2CH2N(tBu)OH with tri‐tert‐butyl gallium affords a hydroxylaminato complex of the formula [tBu2Ga{ON(tBu)CH2CH2N(H)(tBu)O}], which contains a monoanionic bishydroxylaminato ligand with one anionic and one neutral, but tautomeric aminoxide end, both linked to gallium by their oxygen atoms leading to a seven‐membered ring. The compound was characterised by elemental analysis, 1H and 13C NMR and determination of its crystal structure. 相似文献
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采用紫外吸收光谱法检测十二烷基二苯醚二磺酸钠(SLDED)与十二烷基磺酸钠(SDS)二元复合体系中SLDED的含量。结果表明,在复合溶液中SDS能增强SLDED的吸光度,加入0.500 mmol·L-1复合组分SDS后,0.500 mmol·L-1 SLDED的吸光度由0.631增加至0.682,增幅达8.1%;同时SDS还可以明显降低SLDED在水溶液中的表观临界胶束浓度(cmc),当SDS的浓度从0增加至0.500 mmol·L-1时,SLDED的表观cmc由1.12 mmol·L-1降低至0.702 mmol·L-1。研究结果还表明,羟丙基-β-环糊精(HP-β-CD)能有效消除SDS对SLDED紫外光谱的干扰,加入1.000 mmol·L-1HP-β-CD后,0.500 mmol·L-1 SLDED与0.500 mmol·L-1 SDS/0.500 mmol·L-1 SLDED复合溶液在281 nm处的吸光度分别为0.796和0.798,相差仅0.3%,远低于不添加HP-β-CD时的增幅。在SLDED/SDS复合溶液中,SLDED形成胶束的标准摩尔吉布斯函变ΔγGθm随HP-β-CD浓度的增大而增加,当HP-β-CD浓度由0分别增加至0.400,0.800及1.200 mmol·L-1时,SLDED形成胶束过程的ΔγGθm由-41.098 kJ·mol-1分别增大至-39.833,-39.488和-38.184 kJ·mol-1,表明了相比于形成胶束结构,SLDED分子优先选择与HP-β-CD形成包结物。Job’s实验表明SLDED/HP-β-CD包结物中SLDED与HP-β-CD按物质的量比1∶2进行包结。按包结比1∶2加入HP-β-CD后,紫外光谱法能够准确检测SLDED/SDS复合水溶液中SLDED的含量,方法的回收率为100.8%~101.4%。FTIR及1H-NMR表征表明,SLDED分子进入HP-β-CD分子空腔并形成了包结物,是HP-β-CD消除SDS干扰的本因。 相似文献
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A modular approach to α,β-unsaturated N-aryl ketonitrones has been developed. Specifically, condensation of anilines and enals followed by alkylation of the resulting α,β-unsaturated imines provided N-allyl anilines, which were subjected to oxidation with Oxone® to form α,β-unsaturated N-aryl ketonitrones. This modular approach is general and provides rapid access to diversely substituted α,β-unsaturated N-aryl ketonitrones with a single purification step in good yields. 相似文献
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The synthesis of d-cycloserine has been successfully accomplished from the readily available d-serine through three simple and efficient routes. In each synthetic strategy, cyclization reactions are involved as the key step, and one-pot processes are employed. The simple treatment and mild reaction conditions are attractive features in this methodology. 相似文献
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A ring-opening process of 4-imino-l,3-thiazetidin-2-ones with NH_2OH·HC1 was described for the first time.Two different scaffolds of imidodicarbonic diamide were obtained selectively in good yields in the presence of organic base.The obtained imidodicarbonic diamides were demonstrated by X-ray diffraction analysis. 相似文献
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靛蓝二磺酸钠褪色分光光度法测定水中臭氧 总被引:1,自引:0,他引:1
在pH 2.0的磷酸-磷酸氢二钠缓冲溶液中,臭氧可使靛蓝二磺酸钠溶液褪色,且褪色程度与臭氧含量呈线性关系,据此提出了测定水中臭氧的方法。试验结果表明:靛蓝二磺酸钠的最大吸收波长为610 nm,臭氧的质量浓度在0.12~3.0 mg.L-1范围内与吸光度变化值呈线性,表观摩尔吸光率为1.8×104L.mol-1.cm-1。应用此方法测定了水中臭氧的含量,测得相对标准偏差(n=20)在0.6%~2.8%之间。 相似文献