Chemical Forums
Chemistry Forums for Students => Organic Chemistry Forum => Topic started by: xshadow on October 01, 2020, 08:31:06 AM
-
Hi!
I have to answer at this question:
" Explain why the -CH2- group ot the benzyltriphenyl phosphonium salt gives a doublet with H-NMR spectrum"
The -CH2- group don't see any Hydrogen in α position
So that doublet can't be come from a short range coupling
Can it be a long range coupling because we have some insaturations?
I suppose this:
(https://i.imgur.com/ij7Eb2b.jpg)
Thanks
-
What is the spin of phosphorous-31?
-
What is the spin of phosphorous-31?
I think is 1/2
But here we have a H-NMR spectrum...
I think coupling with other species different from Hydrogen cannot be seen with the Hz for H1[/sup
Is it wrong?
-
One is not observing the other nucleus; one is observing coupling to another nucleus. A good example is the C-13 satellite peaks in the H-1 spectrum. One of the joys of phosphorus chemistry is seeing beautiful coupling to other nuclei.
-
One is not observing the other nucleus; one is observing coupling to another nucleus. A good example is the C-13 satellite peaks in the H-1 spectrum. One of the joys of phosphorus chemistry is seeing beautiful coupling to other nuclei.
so that doublet arise from the coupling between the -CH2- and the phosphorus nucleus....
I didn't know this!!
(Usually I've seen 1H NMR spectrum where hydrgen nucleus is coupled with another hydrogen nucleus ...and I ignored all other type of coupling)
-
It would be difficult to decouple the other nuclei; therefore, one usually observes it. The coupling constants can give useful conformational information.
-
One is not observing the other nucleus; one is observing coupling to another nucleus. A good example is the C-13 satellite peaks in the H-1 spectrum. One of the joys of phosphorus chemistry is seeing beautiful coupling to other nuclei.
I agree, its a nice thing about phosphoros-chemistry! Its great with fluorine-chemistry as well for the same reason.
-
Oh understand
Thanks all!!