[discodermolide]

As I said I think the integration is not quite correct. at 2.70 there are 2 hydrogens attached.
The lines tell you how many hydrogen atoms are on the adjacent carbon atom, formula n+1, where n is the number of hydrogens. The intensity of the lines follows Pascal's triangle, 1,   1,1    1, 2, 1,    1,3,3,1 and so on. So for example if you saw 4 lines with intensities of 1,3,3,1 (a quartet) it's neighbouring C atom has 3 hydrogens attached to it. That is n+1 where n is the number of neighbouring hydrogens.

[mjoa123]

As I said I think the integration is not quite correct. at 2.70 there are 2 hydrogens attached.
The lines tell you how many hydrogen atoms are on the adjacent carbon atom, formula n+1, where n is the number of hydrogens. The intensity of the lines follows Pascal's triangle, 1,   1,1    1, 2, 1,    1,3,3,1 and so on. So for example if you saw 4 lines with intensities of 1,3,3,1 (a quartet) it's neighbouring C atom has 3 hydrogens attached to it. That is n+1 where n is the number of neighbouring hydrogens.

So I now know that the compound starts off with a Carbon atom with 3 Hydrogen atoms attached to it. On the NMR there is a long single line that's a 2.0521 ppm. I can't remember if they told me if that was chloroform or water or if that is an actual part of the compound. So it's just one line, so I assume that there is just one of it. It has to be either C, H or O. I may be totally off here though?

[mjoa123]

Is it methyl propanoate (C4O8H2)? I think I have narrowed it down to a few that could possibly be it but I can't find any decisive one.

[discodermolide]

No it's not methyl propionate, but good guess faulty reasoning.
So you have a CH₃ group in your molecule which displays as a triplet, this means it is next to a carbon atom that has 2 hydrogens on it.
The signal at 2.05 is neither water nor chloroform.
It is a singlet, meaning it has neighbours with atoms not having hydrogen to them, so what could that be?
And the signal with 5 lines? What does that tell you?
 

[mjoa123]

No it's not methyl propionate, but good guess faulty reasoning.
So you have a CH₃ group in your molecule which displays as a triplet, this means it is next to a carbon atom that has 2 hydrogens on it.
The signal at 2.05 is neither water nor chloroform.
It is a singlet, meaning it has neighbours with atoms not having hydrogen to them, so what could that be?
And the signal with 5 lines? What does that tell you?

Hmmm.. well doesn't methyl propionate have 2 H atoms on the 2nd carbon?

[discodermolide]

What does the IR tell you?

[mjoa123]

What does the IR tell you?

I think it tells me where the C-O groups are? If I remember correctly. In the previous post, were you saying the 2nd carbon has 2 H atoms on it or that it does not? Is the first carbon atom with 3 H atoms attached the singlet, meaning the carbon next to it has an Oxygen atom attached?

[orgopete]

Okay, you are close. Let's review. There are two methyl groups, one has a CH2 attached and the other, none. There are two other CH2 groups. Logically, they are connected. I think you had that. I presume you learned from the IR a C=O and  C-O bond were present, also consistent. If you look at a table of chemical shifts, an atom attached to a oxygen atom will be shifted much further down than one attached to a carbon. One of the CH2 groups is shifted to about 4 ppm. With your MF, what is he compound?

[discodermolide]

No I said that the first carbon is attached to a carbon carrying 2 hydrogens.
The singlet corresponds to a CH₃ group but has no neighbours having carbons carrying hydrogen atoms. Which is why I asked about the IR.

[mjoa123]

But isn't the CH3, the carbon in CH3 the first carbon atom?

[discodermolide]

There are two CH₃ groups in this molecule.
Look at Orgopete's summary.

[mjoa123]

There are two CH₃ groups in this molecule.
Look at Orgopete's summary.

Hmmm.. well I know there is a CH3 at the beginning and in the end, but doesn't that mean the first carbon has 3 Hydrogen atoms attached? So how could the first carbon have 2 hydrogens attached?

[discodermolide]

You are not reading carefully. I said that one of the CH₃ groups is attached to a carbon carrying two hydrogens, a CH₂ group.

So you have CH₃-CH₂-Unknown-Unknown-Unknown-CH₃.
Look at the IR

[mjoa123]

Hmmm.. I think it's methyl butanoate? It also matches my boiling point. Is it methyl butanoate or methyl butyrate?

[discodermolide]

No it's not them. I can see you reasoning.
Go back to
http://en.wikipedia.org/wiki/Proton_NMR
and look at the table.
Think about the triplet at 4.1 ppm. What does that mean?