Oxymercuration-demercuration is an indirect method of addition of water to alkene for making alcohol.
The reagents used in this reaction are
1)Hg2+ salt (mostly mercuric acetate used)
2)water as a neucleophile (gives OH-)
3)NaBH4 (gives H-)
Alkene reacts with mercuric acetate to form an organomercury intermediate, which reacts with NaBH4 and gets reduced to alcohol.
In unsymmetrical alkene MARKOVNIKOV RULE IS FOLLOWED. But
There is NO formation of Carbonation, so no rearrangements are possible.
Example of a overall reaction:
CH3CH=CH3 + reagents 1,2&3 ----> CH3CH(OH)CH3
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