In the case of the example given below, the coupling of two different
alkyl radicals to form a carbon-carbon bond in a synthesis is not an
effective way to carry out that step. Too many side reactions (various
other couplings, etc) are possible. Selectivity would be low. Also,
chain terminating steps should not be considered synthetically useful in
general, since they lead to demise of the reaction.
Well, that's all I have time to write this a.m. before the exam.
CBF
On Fri, 6 Dec 1996 mcgillsa@PLU.edu wrote:
> Candi,
>
> I was wondering the same thing myself.... I did the reaction that way too.
> I wonder what's right, since no one has responded. :)
> Shana
>
> On Mon, 2 Dec 1996 ulamce@plu.edu wrote:
>
> > HI there! I had a question about 9.26a&b. The problem says to outline a
> > synthesis for different compounds. For a and b, the answer book uses a
> > lithium dialkylcuprate reaction to combine the the alkyl chains, using
> > radical reactions to produce the alkyl halides for the (R2)LiCu reaction.
> > My question is why you can't just have the two alkane chains react with
> > radicals to produce alkyl radicals, and then have the two alkyl radicals
> > combine to form the longer alkyl chain? Wouldn't this be a possible
> > chain-terminating step that could happen in the reaction if you had both
> > alkanes present originally in the mixture?
> >
> > Hopefully someone understood what I was babling about.... =)
> >
> > ulamce
> >
> >
>
>
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