Couple a hydroboration with more than one reaction
Lets say you need to convert an alkene into an anti-Markovnikov type product but instead of attaching one functional group to the less substituted
alkenyl carbon, you need to attach 2. So lets say your reagent is isobutylene:
and you want to convert it into 2-chloro-3-methylbutane:
or 1-chloroisobutan-1-ol:
how would you do it? I recently learned about hydroborations and how the organoborane can be converted into other functional groups such as hydroxy,
amino and halide groups. Is there a way to attach another substituent to the carbon before replacing the boron group with the other substituent? For
example if I wanted to synthesise the first product I mentioned, would there be a way to exploit the unusual situation of the carbon having a boron
atom attached to it and somehow attach a methyl group to the carbon before performing the chlorination reaction? Or if I was after the 2nd product,
could I somehow chlorinate the atom before performing the oxidation part of the hydroboration-oxidation reaction? Maybe there are better reactions
that hydroborations for this kinda thing so if you know of any different anti-Markovnikov electrophilic additions that could be used to do this can
you inform me about them. I just want to know how to attach more than one substituent to the less substituted carbon of an alkene.
[Edited on 19-12-2011 by JibbyDee]
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