Tandem Oxidation Processes: The Direct Conversion of Activated Alcohols into Oximes; Synthesis of Citaldoxime
作者:Richard J. Taylor、Hisashi Kanno
DOI:10.1055/s-2002-32949
日期:——
The direct conversion of primary alcohols into oximes is reported using manganese dioxide and alkoxylamines/hydroxylamine as their hydrochloride salts or supported on Amberlyst 15. This transformation has been applied to a range of benzylic, allylic and propargylic alcohols and utilised to prepare the natural product citaldoxime.
Alkylative amination of aldehydes was achieved via a carbon-carbon bondformation by the intermolecular alkyl radical addition to the carbon-nitrogen doublebond of oxime ethers generated in situ from aldehydes and benzyloxyamine. Alkyl radical addition to oxime ethers via a route involving the iodine atom-transfer process was found to be largely dependent on the reaction temperature and eliminated
Sulfonyl oxime ethers undergo facile radical substitutions with various amines to yield the corresponding oxime ethers. An efficient arylation of sulfonyl oxime ethers was accomplished under ambient temperature and metal-free conditions, with a wide range of functional group tolerance. Mechanistic investigations indicate that a phenyl radical is involved in the catalytic cycle.