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楼主  发表于: 2010-06-03 17:44

 化学合成323单词的文章需要翻译 有重谢

300愚币的
Experiment 5.78 HEXANEDIAL
trans-Cyclohexane-l,2-diol (232mg, Expt 5.48) and sodium metaperiodate supported on silica gel (6.1 g 10% loading. Section 4.2.55, p. 455) are stirred in dichloromethane (15ml) (1) for 3 hours at 20~C. The solids are then filtered off and washed with dichloromethane (2 x 10 ml). Evaporation of the solvent from the combined filtrate and washings gives a clear oil (185mg   80%) which is pure dial.
   Note. (1) The dichloromethane is distilled from phosphorus pentoxide and stored over molecular sieves.
5.7.3 THE OZONOLYSIS OF SUITABLY SUBSTITUTED ALKENES
Oxidation of alkenes with ozone followed by cleavage of the resulting ozonides to carbonyl compounds is widely used for the determination of structure of unsaturated compounds. The ozonolysis technique is described in detail in Section 2.17.4, p. 103.
   For-preparative purposes the cleavage of the ozonide is best carried out by catalytic hydrogenation over palladium hydroxide:on-calcium carbonate a catalyst system which does not hydrogenate the aldehydic products; the yield of the latter are usually fairly good. An alternative procedure for the decomposi-tion of the ozonide is treatment with dimethylsulphide in methanol; the use of the less obnoxious thiourea is a good alternative
   Two examples of preparative ozonolysis are given (Expt 5.79). In the first cyclohexene is subjected to ozonolysis in ethyl acetate to provide a convenient synthesis of theα,ω-dicarbonyl compound, adipaldehyde. In the second, the substrate is oleic acid, which yields two aldehydic fragments, non and azelaic hemialdehyde.
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1楼  发表于: 2010-06-05 09:08
这篇和那篇重了,你可以先给300,另外一篇少给300即可。

实验5.78 己二醛
反式1,2-环己二醇(232mg,实验5.48),负载在硅凝胶上的高碘酸钠(6.1g,含量10%,4.2.55节,455页),20℃下加入二氯甲烷(15ml)中搅拌3小时。反应后得到的固体进行过滤并用二氯甲烷(2 x 10 ml)洗涤,将过滤物与洗涤物合并,蒸干溶剂后得到纯的二醛产物,呈清亮油状(185mg,产率80%)。
注意事项(1)二氯甲烷加入五氧化二磷蒸馏,加入分子筛储存。
5.7.3 选择合适的取代烯烃进行臭氧化
烯烃用臭氧氧化,通过分裂反应得到的羰基化合物可以用于确定不饱和化合物的结构。臭氧化技术在103页2.17.4节详细介绍。
出于制备的目的,臭氧化物的分裂最好在氢氧化钯的催化氢化作用下进行:通常在碳酸钙表面进行,此时体系不能氢化醛类物质;后者的产率通常很高。另一种分解臭氧的方法是用二甲基硫醚在甲醇体系中进行处理,使用性小的硫脲是另一个好的选择。下面给出两个臭氧化反应的制备例子(实验5.79)。第一个例子中,环己烯在乙酸乙酯中发生臭氧分解能够方便地合成α,ω-二羰基化合物,己二醛。第二个例子中,反应底物是油酸,产生两种含醛的片断,壬醛和壬醛酸。
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