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关键词： 有机合成   催化剂   碘  

摘要： 碘在有机合成中有着广泛的应用。碘是一种温和的Lewis酸,因其廉价、易得、无毒害,并在温和的条件下能高产率、高选择性地合成各种有机中间体而引起广泛地关注。文章综述了近年来碘在催化酰化反应、合成胺类化合物反应以及在其它合成反应中的应用。参考文献19篇。

关键词： Alcohols   Organic synthesis   Organic compounds   Nitrogen compounds   Cyclization  

摘要： An intramolecular iminoacetonitrile [4 + 2] cycloaddition functions as the key step in an efficient total synthesis of the quinolizidine alkaloid (-)-217A.

关键词： 课程建设   多步骤有机合成实验   能力   改革  

摘要： 本文主要介绍了多步骤有机合成实验教学改革的目的,基本作法以及实施的效果和体会.

关键词： 异丁醇   危险化学品   知识问答   甲基丙醇   透明液体   有机合成   分子量   戊醇   溶剂  

摘要： 异丁醇又名2-甲基丙醇。五色透明液体，微有戊醇味。主要用作溶剂及有机合成。分子量为74．12，熔点为-108℃，沸点为107.9℃，溶于水，易溶于醇。醚。

关键词： 研发中心   精化   中国   高科技园区   高分子化学   投资规模   有机合成   物理化学   专业知识  

摘要： 投资规模超过2000万美元的汽巴精化上海研发中心已于今年4月正式启动。据介绍，这座位于上海漕泾高科技园区的研发中心将会聚集来自汽巴精化全球的近100名科学家。该中心占地约6000m^2，主要任务是集有机合成、物理化学、高分子化学、光化学和分析化学方面的专业知识以及在应用领域的专家技术，为区域和全球市场开发新的产品，提供高附加值的技术方案。

关键词： 相转移催化剂   催化活性   相转移催化法   双环   庚烷   简化工艺   有机合成   合成农药   加成反应   二氯卡宾   PTS   高产率   高分子   季铵盐   环己烯   应用   醇  

摘要： 相转移催化剂,简称PrS,它是项能够简化工艺,提高产率的有机合成新技术,相转移催化法在近十年来愈来愈受到人们的广泛关注,有的已在工业上得到了推广[1],特别是在某些高分子合成农药和医药的某些昂贵的产品的合成[3],卡宾的制备和应用等领域中,相转移催化法必将发挥愈来愈大的作用.相转移催化法的研究,其关键在于相转移催化剂的选择和应用.实验中我们选择了季铵盐、聚醇、聚醚三类价廉易得的相转移催化剂,研究了氯仿在碱作用下生成的二氯卡宾与环己烯的加成反应.

关键词： DMP试剂   有机合成   应用  

摘要： 重点综述了12-I-53-乙酸基高碘酸盐(DMP试剂)在有机合成中6类重要应用,并对其在有机合成领域的应用前景作了展望。

关键词： Chemistry laboratory   Ketones   ethyl acetoacetate   organic chemistry   organic   Saccharomyces cerevisiae   Enzymes   Amines  

摘要： Important and interesting additions to the undergraduate organic laboratoryare biological reaction systems that can enhance stereochemical outcomes of common *** is a vital part of the organic chemistry curriculum and is often one ofthe most challenging for the organic *** organic chemistry laboratory textbooks touchlightly on this subject,usually having one or two experiments pertaining to stereochemical controland *** reduction of ethyl acetoacetate and resolution of amines with chiral resolvingagents are such examples,found in today's laboratory texts (1).

关键词： transition metals   hydride and methyl derivatives   direct and transfer epimetallation   alkylidenes in C-C bond formation   Ziegler-Natta and ROMP catalysts  

摘要： A broad survey of both the simple and double decomposition modes of transition metal alkyls has been undertaken. From the two main processes of C-M bond rupture, homolysis, and beta-metal hydride elimination, the following modes of decomposition and types of useful reagents generated can be distinguished: 1) reductive decomposition of RnMEm-n to yield subvalent, carbene- or free-radical-like MEm-n, which can cleave pi- or (sigma-bonds by direct epimetallation;2) beta-metal hydride elimination to produce hydrometallating agents;3) combined reductive and beta-metal hydride eliminations to produce anionic, and hence more nucleophilic, epimetallating agents;4) alpha-metal hydride elimination thought to be involved in the transition state leading to C-C bond coupling from (RR'HC)(2)ME2 derivatives;5) alpha,mu-elimination from lithiated RHC(Li)-MEn-1, which produces alkylidenes, RHC = MEn-2, capable of ROMP catalysis;6) metal-hydrogen metathesis, whereby sufficiently acidic C-H bonds become C-M bonds;7) metal-metal metathesis, whereby RR'ME2 undergoes an equilibrating redistribution reaction to form R2ME2 and R'2ME2;8) transfer epimetallation, in which epimetallation (point 1) is achieved with R2ME2 in one step by transfer of ME2 to the substrate with the concomitant loss of R groups;and 9) transfer epimetallation of olefins by R2TiE2 in hydrocarbons to produce titana(IV)cyclopropanes, which serve as active sites in Ziegler-Natta polymerization. In each situation, the reaction-mechanistic features are analyzed in terms of existing experimental data and evidence.

关键词： MOLECULAR weights   PHYSICAL & theoretical chemistry   HETEROCYCLIC compounds   ORGANIC cyclic compounds   CHEMICAL decomposition   SCISSION (Chemistry)  

摘要： Solid-phase synthetic approaches,pioneered by Bruce Merrifield in 1963,inconjunction with combinatorial methods developed over the past 20 years are highly efficient meansfor the production of tens of thousands of individual compounds and/or mixture-based libraries madeup of millions of *** conjunction with high-throughput biological screening,combinatorialapproaches are now routinely used in the search for new pharmaceutical lead *** currentlyutilized solid-phase organic synthetic supports require that the desired syntheticcompound(s),whether they are low-molecular weight acyclic or heterocycliccompounds,peptidomimetics,peptides,or oligonucleotides,etc.,must be cleaved from the support and,asa final step,separated from the spent support.