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CMC负载稀土催化剂是由CMC和异丙氧基稀土制得。这种固体Lewis酸催化剂被用在比较温和的条件下合成取代的咪唑类化合物。相比于昂贵的稀土Lewis酸Ln(OTf)3,廉价的CMC负载稀土催化剂也显示出了很高的催化活性。此外,这种催化剂还具有易于回收和重复使用五次以上没有明显失活的优点。 相似文献
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Heck reaction of iodoarenes with methyl acrylate, catalyzed by cyclolmlladated complexes of tertiary arylamines, was investi-gated in ionic liquid 1-butyl-3-metylimidazolium tetratluorobo-rate ([Bmim] BF4^- ). The products can be isolated convenient-ly from the ionic liquid-catalyst system. The catalysts could be reused for more than 10 times still with satisfactory catalytic ac-tivity. 相似文献
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Homocoupling of aryl iodides catalyzed by cyclopalladated complexes of tertiary arylamines gives symmetric biaryls with good yields in DMA or ionic liquid [Bmim]BF4. This catalytic alternative of the Ullmann reaction has proved to be sensitive to both electronic and steric factors of substrates. 相似文献
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结合“高精度炸药件制造技术”的实施,开展了复杂型面炸药件计算机辅助制造技术的研究。首先根据WF74VH五轴加工中心机床结构及数控系统特点,完成了该机床的后置处理,形成了与之相匹配的后置处理文件;同时对固定轴铣、变轴铣的计算机辅助编程进行了深入的研究,使多轴联动加工技术成功运用于复杂型面炸药部件的数控加工,大大提高了我所炸药机械加工数控编程能力。 相似文献
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Highly selective dimerization of α-methylstyrene (AMS) was effected using a Broensted acidic ionic liquid,[Hmim]^ BF4^-, as solvent as well as catalyst, providing the industrial high-value olefin, 2,4-diphenyl-4-methyl-1-pentene (1-PT). The desired dimer 1-PT could be obtained in 90% yield at 96% conversion in the dimerization of AMS under optimized conditions. Features of the procedure include use of readily available ionic liquid-catalyst,exclusion of volatile organic solvents, higher selectivity and efficiency for 1-PT. 相似文献
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IntroductionAsoneofthemostimportantC—Cformationreactionsandone stepmethodforthearylationofolefins ,Heckre actionhasattractedmuchinterest.1However ,thereactionusuallyneedsarelativelylargeamountofpalladiumcata lyst (>1mol%)forsatisfactoryconversions .Recently ,avarietyofpalladacyclesincorporatingcyclometallatedphos phine ,2 phosphite ,3 carbene ,4 imine5andoxime6havebeenreported .Theuseofcatalystswithnitrogen basedligandswasdemonstratedtopossessveryhighactivity .Wehavereportedthecyclopalladat… 相似文献
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