1988 Fiscal Year Final Research Report Summary
Organic Synthesis Using Electrochemical Functionalization of an Unactivated Carbon Position
Grant-in-Aid for General Scientific Research (C)
|Allocation Type||Single-year Grants |
|Research Institution||Hokkaido University |
TOKUDA Masao Faculty of Engineering, Hokkaido University, 工学部, 助教授 (80001296)
ORITO Kazuhiko Faculty of Engineering, Hokkaido University, 工学部, 助手 (20109482)
SUGINOME Hiroshi Faculty of Engineering, Hokkaido University, 工学部, 教授 (00000779)
|Project Period (FY)
1987 – 1988
|Keywords||Functionalization of Unactivated Carbon Position / Remote Functionalization / Anodic Acetamidation / Anodic Oxidation / Steroid / アリル位酸化|
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.
Research Products (10results)