共查询到16条相似文献,搜索用时 140 毫秒
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以KOH/LiCI催化合成二苯并-14-冠-4,再经过适当比例混酸催化,与癸二酸缩聚合成聚1,10-癸二酮二苯并-14-冠-4,有效地缩短了反应时间,降低了生产成本.明显提高了收率。 相似文献
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以羟甲基-12-冠-4和1,6-二溴己烷、1,10-二溴癸烷为原料,在KH催化下,分别合成一溴己氧基12-冠-4和一溴癸氧基12-冠-4;将一溴癸氧基12-冠-4与硫脲加到无水乙醇中,反应过夜合成至今还未见报道的巯基癸氧基12-冠-4,并对其进行表征确认。在不同的pH条件下,分别比较了3种化合物对Li+和Na+的选择配合情况。结果表明,一溴己氧基12-冠-4和一溴癸氧基12-冠-4对Li的配合比都是1∶1,在氯仿中的萃取率不随冠醚环上支链的长短变化而变化,但随pH的增大而增大,达峰值97.69%后趋于稳定;巯基癸氧基12-冠-4由于巯基水解的效应对Li配合物的萃取能力稍差,且随pH的增大而减小,在75.76%后趋于稳定。同时它们对钠的萃取能力则较差。由此可见,12-冠-4对Li具有很好的选择配合能力,该研究为冠醚更广应用提供了一定的基础。 相似文献
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通过苯并-15-冠-5与浓H2SO4的磺化反应得到4'-磺酸苯并-15-冠-5,再经CaCO3和Na2CO3中和得到其钠盐,接着与SOCl2发生酰氯化反应合成了4'-氯磺酰苯并-15-冠-5,后者与取代苯肼在回流条件下发生取代反应制得了一系列未见文献报道的冠醚化磺酰肼类化合物,产物经IR、1HNMR、13CNMR 和元素分析确证了其结构,利用紫外-可见吸收光谱考察了其对不同阳离子的识别作用,结果表明,该系列化合物对Cu2+和Fe3+有较明显的识别作用,且与受体分子形成1∶1型主-客体配合物. 相似文献
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自从冠醚于六十年代末问世以来,科学家们对它进行了大量的研究。它以遮盖力大,对金属离子络合性能好而著称于化学领域。在感光化学领域,它的主要应用在于对乳剂晶体的尺寸及分布产生影响,使之均一,且颗粒增大;作为调变剂,促进外延乳剂晶体的生长;提高乳剂的感光性能。 相似文献
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Rima Biswas Tamal Banerjee Pallab Ghosh Sheikh Musharaf Ali 《American Institute of Chemical Engineers》2019,65(9):e16686
Stripping of metal ions (i.e., Cs+ and Na+) in presence of ionophore such as dibenzo-18-crown-6, (DB18C6) from the ionic liquid phase to the aqueous nitric acid phase by molecular dynamics simulation is reported. The experimentally determined stripping percentages of Na+ (i.e., 43.4, 38.5, 34.4, and 31.9%) were found to be higher than the same for Cs+ (i.e., 32.6, 32.0, 31.3, and 30.2%). The nonbonded and the hydrogen bond energies between Na+ and water (i.e., −356.41 and −363.77 kcal/mol) were higher when compared with Cs+ (i.e., −212.43 and −221.04 kcal/mol). The spatial distribution functions further confirmed that the surfaces of Na+ were very closely distributed around the active sides of water whereas for Cs+, it was distributed very far from the water molecules. In the penultimate section, the effect of methanol to the aqueous phase was studied so as to enhance the extraction efficiency of the complex. 相似文献
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采用超声波反应器,以邻苯二酚、二甘醇和对甲基苯磺酰氯等为原料,二甲亚砜为溶剂,氢氧化钾为催化剂兼模板剂,合成二苯并-18-冠-6(DB18C6)。产物经IR和^1HNMR表征。合成收率达到42%。较之传统方法具有操作简单、反应时间短、反应条件温和等优势。 相似文献
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Two functional crown ether initiator, bis[4′-(2-bromobutyryl)]dibenzo-18-crown-6 (BBDC) was synthesized through the condensation of dibenzo-18-crown-6 with 2-bromobutyric acid in the presence of polyphosphoric acid. Atom transfer radical polymerizations of styrene (St), methyl acrylate, methyl methacrylate and butyl acrylate were carried out in bulk to produce the polymers with well-controlled molecular weights and narrow molecular weight distributions (1.12-1.32). Based on 1H NMR results, both the two bromides of BBDC initiated the polymerizations. The well-defined two-armed polymers were self-assemblized in the presence of potassium cations. Their morphologies of the film obtained were studied by atomic force microscopy with tapping mode. 相似文献