ortho-Mercuration of ferrocenylimines

The mercuration of a series of aryliminomethylferrocenes occurred predominantly in an ortho-position of the substituted ferrocenyl ring to yield 2-mercurated ferrocenylimines. The regiospecificity of this reaction suggests that the mercury is directed into the ortho-position by coordination of the mercury to imino nitrogen with subsequent electrophilic substitution. The chromatographic and spectral properties of the 2-mercurated products show the presence of an intramolecular N → Hg coordination via the five-membered ring in these molecules, which was further confirmed by the single-crystal structure analysis of 2-chloromercuro-1-[(4-methoxyphenylimino)methyl]ferrocene.