There's something confusing on this sheet. There's some data listed, one clearly pasted on, not that that's abnormal. But it lists dmso (assuming d6-DMSO) as the solvent, and also CDCl3 in the other one. So, that begs the question, which solvent was used? The peak at 2.5 suggests it's DMSO. DMSO should be a quintet, but a pretty sharp one, I think, so I think that's fine. CDCl3 would have a peak at 7.24, which would be buried in the aromatic H's.
The shifts from the two phenyl groups should be identical since they're on an achiral carbon. Thus, I think you should see three separate peaks from those 10 carbons; one doublet, and two triplets. the para-hydrogen will have a separate triplet from the meta-hydrogen, and the ortho-hydrogen being the doublet. the para-hydrogen would integrate to 2, and the ortho and meta hydrogens to 4 (edited to fix). It's hard to tell from the resolution, but the region 7.2-7.6 seems to show this? However, if CDCl3 was the solvent, there should have been a singlet at 7.24, and usually NMR solutions are prepared in such a way so that the solvent peak is obvious.
The benzyllic hydrogen should be shifted upfield from both the phenyls and the sulfoxide, and should be a singlet. It seems reasonable that the peak at 5.4 is this hydrogen.
Now, there's two hydrogen's on the carbon between the sulfoxide and carbonyl. I don't know if they would have unique peaks, or what, so the really weird peak at 7.65 could be one of these hydrogens. I don't really know what sulfoxide groups do here, but on first pass I would think there wouldn't be two unique peaks since the carbon is achiral. But there could be some strange coupling. Or, it could be that the 7.65 peak is something totally unrelated, and both hydrogens are found in region around 3.25.
Now the only thing left is the amine hydrogens. Those are tricky to assign, since the peak would be weaker, I think, because deuterium should be able to more easily exchange with those hydrogens. Maybe they're in the region around 3.25? I would expect a singlet here, but I also don't know if amine hydrogens would have extra splitting.
I can't assign the peak at 7.65 or those in the 3.25 region with a lot of confidence; you might expect if you had adrafinil, with an OH on the amine, that there would be an additional peak and possibly more splitting on the amine hydrogen. But then again, the signal from the OH might be very weak since it's more easily exchanged with deuterium. Maybe, if you had adrafinil, one of the hydroxylamine hydrogens could be shifted a lot more.
What would be good would be a GC/MS spectrum, I think. If you get a peak with a mass 16 higher than you expect, well, then, you got adrafinil there, fella. I guess I should have started with that. If you then were sure you had modafinil, racemic or not, then you could do an optical polarization measurement to see if you have R or S, or mix.
Edited by PhysicsMaestro, 28 February 2013 - 02:02 PM.