Alkene oxymercuration is closely analogous to halohydrin formation.
The reaction is initiated by electrophilic addition if Hg2+(mercuric) ion to the alkene to give an intermediate mercurinium ion, whose structure resembles that of a bromonium ion (Figure 7.5), Nucleophilic attack of water. Followed by loss of a proton, then yields a stable organomercury addition product. The final step, reaction of theorganomercury compound with sodium boro-hydride, is nt fully understood but appears to involve radicals, Note that