[DoctorDomo]

For example:

the intensity drops below the baseline for some of the peaks. Only some of them. And I've noticed at my college, they run 2 fluorine spectra for you, 1 is normal, the other features these negative peaks. Cant find any info on what they mean.

[discodermolide]

This spectrum has not ben phased properly, that is why some of the peak appears below the baseline.

[DoctorDomo]

This spectrum has not ben phased properly, that is why some of the peak appears below the baseline.

Do extra multiplets appear when the baseline is not corrected? I notice the phase corrected spectra I have, show less multiplets. I can't seem to correct the phase of this particular spectrum (Im using ACD 1d NMR processor). When I correct one part of the spectrum, it knocks other sections out of phase. This is the best spectrum the auto phase corrector can obtain. I'll take a look at the FID, but I can't run this NMR again so I'll need to figure out how to correct it. How important is it to correct the phase though? Does it really influence multiplicity (or at least what look like multiplets on the spectrum)?

[discodermolide]

With the ACD software it should be possible to phase this correctly.
This is important. It does not affect the multiplicity but makes the spectrum difficult to interpret. The small peaks may be ¹⁹F-¹³C coupling? As I don't know the structure I can't really say.

[DoctorDomo]

I know that these spectra are proton decoupled, I didn't think of 13C though. Is it not common practice to decouple carbons from fluorine spectra too?

[discodermolide]

No, I don't think so.
You don't say if it's broadband decoupled or not, but I think that just removes the ¹H coupling. I don't really know if that will also remove the ¹³C.