Organic Synthesis Using Electrochemical Functionalization of an Unactivated Carbon Position

1.甾体化合物的远距离乙酰胺化反应研究3 -取代基上带有羰基或间碘苯基的5 -胆甾烷-3-酯在乙腈中于+2.3 +2.7VvsAg/AgNO_3的控制电位下进行阳极氧化，得到相应的6 -乙酰胺化胆甾烷酯，产率为7.26%。通过与由胆固醇经9步反应制得的真实样品的比较，证实了产物的结构和立体化学，总收率为4.8%。通过循环伏安法的研究提出了分子内提取未活化氢的反应途径.胆甾烷和雄甾烷的阳极乙酰酰胺化：无3 -取代基的甾体在乙腈中的阳极氧化也得到6 -乙酰酰胺化的胆甾烷和雄甾烷。在反应中加入2-丁酮可使产物收率提高到36%.类固醇的其他功能化：在氯离子存在下，通过间碘苯甲酸5 -胆甾烷-3-基酯的阳极氧化成功地进行了类固醇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的乙酰氧基化.甾体的烯丙基氧化：在氢氧化钠或N-羟基邻苯二甲酰亚胺（NHPI）/氢氧化钠存在下，甾体烯烃的烯丙基亚甲基通过阳极氧化成功转化为羰基.脂肪族化合物的未活性炭的氯化反应。脂肪醇的芳基酯与硫酰氯反应得到远程氯化产物。

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.