Trialkylboranes Subject

It would be presumptuous to attempt to summarize fully the utility of the hydroboration reaction here. There are many variations of this reaction, each designed to accomplish a specific synthetic transformation. A book could be written on the subject. In fact, Professor H. C. Brown has written just such a book. We ll only mention one especially important reaction here, one that leads to a new process for the synthesis of alcohols (recall Problem 9.13, p. 390). When one molecule of trialkylborane is treated with hydrogen peroxide (H2O2) and hydroxide ion (HO ), three molecules of an alcohol are formed along with boric acid (Fig. 9.66). 

Reactions of trialkylboranes with 2-lithio-2-alkyl-l,3-benzodithioles, followed by oxidation, give ketones in good yield. The reaction is far less subject to steric hindrance than the analogous reactions using bis(phenylthio)alkanes (Scheme 10). 

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