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关键词： 有机合成   化学   有机硒   现代   研究和应用   含硒化合物   配位体   催化剂  

摘要： 本书为《通用化学专题丛书》的第208卷，介绍和论述了含硒化合物在催化剂和配位体化合物等领域的研究和应用。

关键词： 有机合成工业   染料   人工   指导作用   推动作用   世界经济   近代科技   知识  

摘要： 染料的合成是化学与工业结合的产物,是科学与技术的结合并对生产起指导作用的先例.它的发现引发了有机合成工业的建立,对近代科技的发展和世界经济的腾飞起到了巨大的推动作用,充分体现了培根提出的"知识就是力量"这一精辟论点.……

关键词： 官能团   高考热点   本意   情况   方法   还原   有机合成   氧化  

摘要： 有机合成是高考热点之一.有机合成中有时会遇到这样的情况:本意只想对某个官能团进行处理(主要为氧化或还原),结果却影响了其他官能团.为了防止处理时对其他官能团的影响,常常对其他官能团采用先保护后恢复的方法.

关键词： 胶团催化   有机合成   复配体系   表面活性剂  

摘要： 胶团催化是近年在有机合成领域迅速发展起来的一项催化技术。该文综述了胶团催化在催化加氢、氧化、水解和亲核取代等有机反应中的应用现状,简要介绍了小分子有机物、电解质和可溶性高分子化合物的加入对胶团催化的影响,展望了胶团催化的发展趋势。引用文献13篇。

关键词： 微波   有机合成   综述  

摘要： 简述了微波有机合成的机理和特点,介绍了近年来微波辐射技术在有机合成中的应用,展望了微波促进有机合成化学的发展方向。参考文献30篇。

关键词： 新型   环化   多官能团   格氏试剂   有机合成   有机镁   制备   化合物   反应   化学  

摘要： 介绍了双格氏试剂、镁杂碳环化合物和含有多官能团的格氏试剂的制备、反应化学及在有机合成中的应用等。

关键词： 化妆品   合成香料   煤焦油   醛类   有机合成   美容用品   防腐剂   微量元素   皮肤过敏   刺激作用  

摘要： 当前，化妆品已成为人们生活中不可缺少的护肤、美容用品，但是各类化妆品中所使用的色素、防腐剂、香料等大多为有机合成物，例如煤焦油类合成香料、醛类系列合成香料，还有含铅、砷和汞等的有毒物质。这些物质有的对皮肤有刺激作用．引起皮肤过敏，有的可引起慢性中毒。近年来，由于一些微量元素在许多方面表现出特殊功能，国内外许多学者已注意到这些微量元素在化妆品中的重要作用。

关键词： CRYSTAL-STRUCTURE   THERMAL-DECOMPOSITION   CYCLIZATION REACTIONS   TRANSITION-METALS   SELF-DIMERIZATION   CARBON BONDS   CHROMIUM   ALKYNES   INSERTION   LIGANDS  

摘要： The chemistry of metal carbene complexes has experienced an enormous development in the past decades. Despite this fact, the use of transition metals as catalysts in reactions involving group 6 Fischer carbene complexes was virtually neglected. Here, we describe how the reactivity of these compounds can be enhanced or modified in the presence of catalytic amounts of a transition metal, leading to new forms of reactivity and others offering clear advantages in terms of efficiency over the uncatalyzed reactions. The key step for these reactions is the transmetalation from the stoichiometric metal carbene reagent to the catalyst. This process generates a new metal-carbene complex that leads to enhanced reactivity of new reaction modes. Two examples of Fischer carbene complexes obtained by transmetalation to Pd and Cu have been isolated during the last 2 years, showing the flexibility if the mechanistic hypothesis for these reactions. The work presented in this Account shows how an area, which was practically unexplored 5 years ago, has emerged as a new and powerful field of research.

关键词： MALDI-MS analysis   organic synthesis on phthalocyanines   piperazine and piperidine derivatives  

摘要： Some small molecules, such as phthalocyanines, capable of exhibiting greatly enhanced capacities and acting as internal tags, are shown to be effective as replacements for polydisperse polyethylene glycols, in soluble polymer-supported type synthesis of some piperidine and piperazine derivatives.

关键词： ENZYMES   ENANTIOSELECTIVE catalysis   CHIRALITY   HYDROLYSIS   CARBOXYLIC acids   KETONES   CHEMICAL reduction  

摘要： During the recent past years,tremendous efforts have been made to establishenantioselective routes for the preparation of enantiomerically pure compounds due to theirimportance in the pharmaceutical,agricultural,and food *** is reflected in the fact thatthe sales of single-enantiomer smallmolecule drugs has reached *** US10 billion ***,the FDA has become increasingly reluctant to permit the introduction of additionalracemic drugs,as these therapies are by definition saddled with 50% of chemical *** arenowadays widely recognized among the most active and selective catalysts for the preparation ofoptically active *** of the factors that account for this popularity are(1)They arechemo-,regio-,and stereoselective,and environmentally friendly.(2)Because of the mild conditionsunder which they operate,enzymatic reactions are affected to a lesser extent by sidereactions(***,racemiza-tion,epimerization,and rearrangement of molecules)as comparedto nonenzymatic ***,organic chemists have been traditionally reluctant to employbiocatalysts in their *** is mainly because,in their natural form,most of the enzymes arevery sensitive catalysts that exert their activity mainly in aqueous solution.