Two-Step Iron(0)-Mediated N-Demethylation of <i>N</i>-Methyl Alkaloids
作者:Gaik B. Kok、Cory C. Pye、Robert D. Singer、Peter J. Scammells
DOI:10.1021/jo1008492
日期:2010.7.16
A mild and simple two-step Fe(0)-mediated N-demethylation of a number of tertiary N-methyl alkaloids is described. The tertiary N-methylamine is first oxidized to the corresponding N-oxide, which is isolated as the hydrochloride salt. Subsequent treatment of the N-oxide hydrochloride with iron powder readily provides the N-demethylated amine. Representative substrates include a number of opiate and tropane alkaloids. Key intermediates in the synthesis of semisynthetic 14-hydroxy pharmaceutical opiates such as oxycodone and oxymorphone are also readily N-demethylated using this method.