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Topic: NMR spectrum problem!  (Read 3160 times)

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Offline bio775

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NMR spectrum problem!
« on: September 14, 2014, 04:32:12 AM »
Hi! how to figure out this C-13 NMR spectrum:
The peak at 25 ppm in the 13C NMR spectrum of B is most likely to be:

I know that at 25 ppm, is the alkane but I don't know which is the right figure. (I have attached the figure)

I am sure the answer is C but just want to double check. Thanks
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Offline kriggy

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Re: NMR spectrum problem!
« Reply #1 on: September 14, 2014, 06:13:35 AM »
I dont think its C, the presence of ester group changes the shift so 25ppm is way too low IMHO (I had carbons like that around 55)
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Offline bio775

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Re: NMR spectrum problem!
« Reply #2 on: September 14, 2014, 06:21:10 AM »
But according to the table at 25 ppm is alkane. So, what do I look for?
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Offline Dan

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Re: NMR spectrum problem!
« Reply #3 on: September 14, 2014, 10:39:13 AM »
Assume R is an alkyl group (say, R = CH3 for example) and draw the options as real compounds - any alkanes?
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