Mercuric trifluoroacetate alkoxymercuration with

We saw in Section 7.4 that alkenes react with water in the presence of mercuric acetate to yield a hvdroxymercuration product. Subsequent treatment with NaBH4 breaks the C-Hg bond and yields the alcohol. A similar alkoxymercuration reaction occurs when an alkenc is treated with an alcohol in the presence of mercuric acetate or, even better, mercuric trifluoroacetate, (Cl CCtitiHg. Demercura-tion by reaction with NaBH4 then yields an ether. The net result is Markovnikov addition of the alcohol to the alkene. 

We have seen that alkenes react with alcohols in the presence of an acid catalyst to form ethers (Section 4.5). Just as the addition of water works better in the presence of mercuric acetate than in the presence of a strong acid, the addition of an alcohol works better in the presence of mercuric acetate. [Mercuric trifluoroacetate, Hg(02CCp3)2, works even better.] This reaction is called alkoxymercuration-reduction. 

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