Re: naming branched alkyls

perkiner@PLU.edu
Tue, 01 Oct 1996 21:01:33 -0800 (PST)

I think that the book means that you number the carbons from the
beginning of the chain, and the one that the group is attached to is the
number of that carbon in the chain. So in your example, the CH3 carbon
would be 1, CH would be 2, and CH2 would be three. Since the methyl
group is attached to the CH, the number 2 is used in naming. I hope this
helps!
Erika

On Tue, 1 Oct 1996 hoffmaja@PLU.edu wrote:

>
> On P.132 it states that to name a branched alkyl the "numbering
> begins at the point where the group is attached to the main chain." Then
> it gives a few examples. Here is one:
> CH3 CH CH2-
> CH3
> The book named this 2-methylpropyl. My question is,if the numbering
> begins at the point where the group is attached, then shouldn't the names
> always start with 1? So in this example the CH3 group is attached to the CH
> so the CH carbon is 1. My thought was that maybe the book means that the
> numbering starts where the H was taken off to make an alkyl group so in
> this case the CH2- is 1 because it is missing it's H. If anyone has some
> insight that could clarify this for me I'd appreciate it!
> Thanks,
> hoffmaja
>