The empty p orbital on the boron makes it susceptible to nucleophilic attack. Alkyl migration can then occur if the nucleophile has a leaving group or electron sink of some sort – this process can be very useful in syntheses.
This pattern of addition-then-migration dominates the reactions of alkylboranes.
Oxidation
In general;
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Hydrogenation
Full cis addition of H2 to an alkene – an alternative to the metal catalysed methods described in the electrophilic addition chapter.
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This can also be carried out on alkenylboranes (which are formed with alkynes plus B-H).
Halogenation
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This also works for I and Br.