Hydration hydroboration-oxidation compared

Alkenes can be hydrated to form alcohols by (1) hydroboration followed by oxidation with alkaline hydrogen peroxide and (2) acid-catalyzed hydration. Compare the product formed from each alkene by sequence (1) with those formed from (2). 

The hydration of alkenes with aqeuous add (Table 6.1, entry 2 Scheme 6.23) or, more conveniently in the laboratory, by oxymercuration (Table 6.1, entry 6) and reduction (Scheme 6.24), can be usefully compared with oxidative hydroboration (Table 6.1, entry 17 Scheme 6.25) as alternative synthetic techniques for preparation of alcohols. 

Three of the six reactions are well suited for the synthesis of alcohols acid-catalyzed hydration, oxymercuration (after reduction of the C-Hg bond by NaBHi), and hydroboration (by oxidation of the C-B bond by H2O2). Compare the alcohol from hydration (shown earlier) with that from demer-curation of the oxymercuration product ... 

Oxymercuration/demercuration has thus been suggested as a mild procedure for the Markovnikov hydration of carbon-carbon double bonds. As shown in Chapter 3, hydroboration followed by oxidation can be used for their hydration contrary to Markovnikov s rule. The two reaction sequences are compared below for 1-hexene ... 

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