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以2-萘酚和80%水合肼为起始原料,经3步反应合成了光学活性的2,2'-二胺-1,1'-联萘。在缚酸剂存在下,将所得光学活性的二胺与甲基丙烯酰氯反应制备得到目标产物(R)-2,2'-二甲基丙烯酰胺-1,1'-联萘。各步产物的结构经核磁分析得到确认。研究了水合肼与2-萘酚的投料比对中间体2-萘肼收率的影响,以及缚酸剂类别、反应温度对目标产物收率的影响,得到了一种适宜的合成工艺路线。 相似文献
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多组分化学反应具有操作简单、高效率和高原子经济性等优点,是一类重要的收敛性合成方法。三氟甲磺酸盐作为新型Lewis酸催化剂有极高的耐热性和耐氧化还原性,水相有机相均可催化,因温和、环境友好、可循环使用等特点而受到广泛关注。利用三氟甲磺酸盐催化多组分化学反应已经成为绿色化学的重要手段之一。简要总结了三氟甲磺酸盐催化剂在Strecker反应、Ha-ntzsch反应、Biginelli反应、Mannich反应、Passerini反应和Ugi反应等人名反应中的应用情况,并对其面临的挑战和机遇进行了讨论和展望。 相似文献
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以河南某企业焙砂氰化尾渣为原料,采用NaOH-NaNO3混合熔盐焙烧预处理氰化尾渣后水浸,再进行常规氰化浸出.探究了熔盐添加量、焙烧时间、焙烧温度对氰化渣中SiO2浸出率的影响.试验结果表明上述三个因素对SiO2浸出率影响显著,在最佳焙烧条件:熔盐添加量为尾渣量的50%,焙烧时间2h,焙烧温度500℃下,处理后的渣中金、银品位分别由1.68 g/t、42.7 g/t上升至2.56 g/t、64.8 g/t.金、银氰化浸出率分别为57.6%、68.3%,较直接氰化分别提高了45.1%和60.9%,效果显著. 相似文献
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《分离科学与技术》2012,47(1-3):781-792
Abstract The absorption spectrum of UOCl2 in molten KCl-MgCl2 salts has been measured and compared with that of the related UCl4 spectrum at temperatures up to 932°C and melt compositions of 60–40, 34–66, and 0–100 mol %, respectively, KCl-MgCl2. The species UOCl2 is an important intermediate in the conversion of UO2 to UCl4 and its spectrum provides a means of monitoring the reaction, and other similar reactions, in situ. The solubility of UOCl2 has been determined from absorption spectra and has been found to be 10 to 25 times higher than reported earlier with mole fractions as high as 0.0019 in pure MgCl2 at 932°C. 相似文献
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Nestor Belisario Gomez-Guzman Daniel Lopez-Dominguez Cinthya Dinorah Arrieta-Gonzalez Jan Mayen Eduardo Porcayo-Palafox Jose Guadalupe Chacon-Nava Jose Gonzalo Gonzalez-Rodriguez Jesus Porcayo-Calderon Roberto Ademar Rodriguez-Diaz 《International journal of molecular sciences》2022,23(14)
This study reports the behavior of the Ni20Cr alloy in molten nitrate salts. Its behavior was evaluated in the eutectic mixture called Solar Salt (binary salt) and in a ternary mixture (90% Solar Salt and 10% lanthanum nitrate). The addition of lanthanum nitrate was performed to determine if the presence of the La3+ cation could act as a corrosion inhibitor. Through mass loss and potentiodynamic polarization studies, the effects of both electrolytes on the corrosion resistance of the alloy at 300, 400, and 500 °C and at exposure times of 250, 500, 750, and 1000 h were determined. The results showed an increase in the corrosivity of the ternary salt, due to a decrease in its melting point and an increase in the concentration of nitrate ions. However, it was observed that the La3+ cations formed a protective layer (La2O3) on the alloy surface. In both corrosive media, the Ni20Cr alloy showed excellent corrosion resistance, due to its ability to form protective layers of Cr2O3, NiO, and NiCr2O4, in addition to the presence of a layer of La2O3 in the case of the ternary salt. 相似文献
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熔融盐电镀铝的研究进展 总被引:10,自引:0,他引:10
综述了无机熔融盐电镀铝的各种熔盐组成及相关参数。探讨了无机熔融盐电镀铝的反应机理和铝枝晶的抑制,并介绍了无机熔融盐体系电镀铝的应用和发展前景。 相似文献
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用CaCl2、CuCl2和AgNO3溶液对NaX沸石进行离子交换改性,以所得的CaX、CuX、AgX材料以及NaX和Al2O3为吸附剂,通过吸附性能评价和X射线衍射(XRD)、红外(FT-IR)等表征方法,对吸附法脱除三氟二氯乙烷(R123)中六氟氯丁烯(R1326)杂质进行了研究.结果表明:R1326在各吸附剂上的吸附属于化学吸附;以将R1326脱除至检测限以下、R123不发生明显分解为标准时,CaX的吸附性能最优异,吸附温度最低(220℃),对R1326脱除至检测线以下时的吸附容量达0.066 g·g-1,这与其具有良好的X型分子筛晶体结构和一定的酸性有关.CaX的再生性能不佳,原因是其吸附饱和后丧失了X型分子筛晶体结构. 相似文献
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熔盐在新能源领域的应用 总被引:1,自引:0,他引:1
综述了熔盐在电池(燃料电池、锂电池和热电池)、太阳能热发电等新能源领域的应用及其在生物质热裂解领域的研究动态,评价了熔盐为电解质的燃料电池的工作特点、转换效率和使用寿命,指出了熔融碳酸盐电池是燃料电池的发展方向. 相对于高温固相法制备的锂电池正极材料,熔盐法制备的正极材料的晶体结构和性能得到改善. 在太阳能热发电领域,高温熔盐作为一种低成本、高效率的传热蓄热介质得到了一定的应用. 介绍了熔盐热裂解生物质制取生物油或富氢气体的过程,对比了熔盐组成、裂解条件对产物产率的影响,分析了热裂解机理和动力学,指出熔盐裂解生物质技术的可行性. 最后对熔盐在新能源领域的应用存在的问题进行了分析,并对熔盐应用的发展方向进行了展望. 相似文献
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Single crystals of zircon as large as 0.7 cm and phenacite as large as 1.5 cm were grown from molten alkali metal vanadates and molybdates. The best crystals were obtained by slow cooling melts of Na2 O·3MoO3 or Li2 O·3MoO3 saturated with zircon or phenacite from 1400° to 900°C at a rate of 2° per hour. Crystals grown on a seed by a thermal gradient process contained inclusions although rates up to 1 mm per day were obtained. Zircon crystals could be doped with Nd3+ , Eu3+ , Pr2+ , Fe3+ , Cr3+ , and Mn2+ . The rare earths fluoresced at their characteristic frequencies but no fluorescence was observed from the transition metal ions. Zircon crystals had the characteristic habit, being bounded by m (110) and p (111) faces. Phenacite had a rhombohe-dral habit when grown above 1000° and crystallized as hexagonal needles below that temperature. The solubility of zircon in Na2 O·3MoO3 obeys the Van't Hoff equation with a heat of solution of 5.5 kcal per mole. The heat of solution of zircon and phenacite increased when V2 O5 was substituted for MoO3 in the solvent, increased when NazO was substituted for Li2 O, and increased further when K2 O was substituted. The solubility was higher in solvents containing V2 O5 than in those containing Moo3 . Solvent-solute interactions were strongest when the solvents were strong Lewis acids since zircon and phenacite behave as bases. 相似文献
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Xue-Song Zhang Ya-Ping Han Yong-Min Liang 《Advanced Synthesis \u0026amp; Catalysis》2024,366(3):324-356
Elaborated molecular architectures, especially carbocyclic, heterocyclic, endocyclic, and polycyclic molecular structures, serve as an important class of organic complexes because they are frequently occurring core structural units in a variety of biologically and pharmacologically relevant natural products, drug molecules, agrochemicals, and functional materials. A main challenge of current synthetic approaches is the development of strategically efficient and selective formation of these compounds from easy-to-handle starting materials. The cascade cyclizations of 1,7-enynes have afforded an indispensable method for accessing molecular complexity and diversity, thus highlighting their potential significance in both academic and industrial communities. In the last decades, tremendous efforts have been devoted to discovering convenient routes to access sophisticated annulation derivatives, and a wide range of powerful and straightforward synthetic strategies have been reported. In this review, the latest achievements in the cascade cyclization reactions of 1,7-enynes are summarized, which could be separated into three categories: (1) Visible-light-induced reactions of 1,7-enynes; (2) Metal-free catalyzed reactions of 1,7-enynes; (3) Transition-metal-catalyzed reactions of 1,7-enynes. 相似文献