Hello Everyone,
I did an initial test with F19NMR but my peaks in -CF3 part were overlapped.
My sample was a combination of 4 standard solutions of C4F7COOH, C6F11COOH, C8F15COOH and C10F19COOH which was 100uL plus 100 uL of deuterum MeOH and 800 uL of normal MeOH. I applied 400 NeoNMR which has a specific prob for NMR.
My conclusion is that I have to apply higher frequency like 600MHz or 900 MHZ.
Please let me know if you have any ideas to get a clear signal with this method.
I appreciate any assistance.
Faranak
Faranak,
Higher frequency is certainly helpful in resolving overlapping peaks in NMR with close chemical shifts. However, your four compounds are very similar, and even at 900 MHz they still may not be separable. Of course, try this approach if you have access to a high frequency NMR instrument.
Al the same time, I would consider GC or GC-MS for analysing this sort of sample.
Since the molecular weights of the components of your mixture are significantly different, you may try 19F DOSY to distinguish the 19F signals of CF3 groups. See, for example, https://pubs.rsc.org/en/content/articlelanding/2016/cc/c6cc02917e
Dear Vladmir,
I appreciate your comment. I'll try higher frequency.
- Badges
- Science topic
- Similar topics
- Physics
- Condensed Matter Physics
- Solid State Physics
- PEAKS