Organic Synthesis Using Electrochemical Functionalization of an Unactivated Carbon Position

利用未活性碳位置的电化学功能化进行有机合成

基本信息

批准号：
62550620
负责人：
TOKUDA Masao
金额：
$ 1.28万
依托单位：
Hokkaido University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1987
资助国家：
日本
起止时间：
1987 至 1988
项目状态：
已结题

项目摘要

1. Remote acetamidation of steroids by anodic oxidation.Anodic oxidation of 5 -cholestan-3 -yl esters with a carbonyl or a m-iodophenyl group in their 3 -substituents at a controlled potential of +2.3 +2.7V vs Ag/AgNO_3 in acetonitrile gave the corresponding 6 -acetamidated cholestanyl esters in 7 26% yields. The structure and the stereochemistry of the product were confirmed by comparison with an authentic specimen which was prepared via nine steps from cholesterol in a total yield of 4.8%. Reaction pathways involving an intramolecular abstraction of an unactivated hydrogen were proposed from a study of cyclic voltammetry.2. Anodic acetamidation of cholestanes and androstane.Anodic oxidation of the steroids having no 3 -substituents in acetonitrile also gave the 6 -acetamidated cholestanes and androstane. The yield of the product was found to be enhanced to 36% by an addition of 2-butanone.3. Other functionalizations of steroids.Chlorination of the C-9 position of steroids was successfully carried out by anodic oxidation of 5 -cholestan-3 -yl m-iodobenzoate in the presence of chloride ion. Anodic oxidation of steroidal olefins in the presence of Co(OAc)_2 and NaOH lead to a successful acetoxylation of their allylic carbons.4. Allylic oxidation of steroids.An allylic methylene of the steroidal olefins was successfully transformed into a carbonyl group by anodic oxidation in the presence of sodium hydroxide or n-hydroxyphthalimide (NHPI)/sodium hydroxide.5. Chlorinarion of an unactivated carbon of aliphatic compounds.A reaction of the aryl ester of aliphatic alcohol with sulfuryl chloride gave a remote-chlorinated product.

1. 通过阳极氧化对类固醇进行远程乙酰胺化。3-取代基中带有羰基或间碘苯基的 5-胆甾坦-3-基酯在 +2.3 +2.7V 的受控电位（相对于 Ag/AgNO_3）的控制电位下进行阳极氧化乙腈得到相应的6-乙酰胺化胆甾烷酯，产率为7.26%。通过与真实样品的比较，证实了产品的结构和立体化学，该样品由胆固醇经九步制备，总产率为4.8%。通过循环伏安法的研究，提出了分子内夺取未活化氢的反应途径。 2．胆甾烷和雄甾烷的阳极乙酰胺化。乙腈中不具有3-取代基的类固醇的阳极氧化也得到6-乙酰胺化胆甾烷和雄甾烷。发现通过添加2-丁酮，产物的产率提高至36%。3．类固醇的其他功能化。通过在氯离子存在下对5-胆甾坦-3-基间碘苯甲酸酯进行阳极氧化，成功地实现了类固醇C-9位的氯化。在Co(OAc)_2和NaOH存在下，甾体烯烃的阳极氧化导致其烯丙基碳成功乙酰氧基化。 4．类固醇的烯丙基氧化。在氢氧化钠或n-羟基邻苯二甲酰亚胺(NHPI)/氢氧化钠存在下，通过阳极氧化，成功地将类固醇的烯丙基亚甲基转化为羰基。 5．脂肪族化合物的未活性炭的氯化。脂肪醇的芳基酯与磺酰氯反应得到远程氯化产物。