thenextchemist
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I've been struggling to find what molecule is this by looking at the NMR

From the other data I have been given (IR and C nmr), its definitely an alcohol and it has an alkene group in it. It's hard because I'm not sure where the 5.9 group comes from - the multiplet.


Thanks in advance!

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Pigster
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pent-4-en-2-ol?

The 5.75 peak would be C4.
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_NMcC_
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Also get pent-4-en-2-ol.

The key bit in my opinion are the two Multiplets at 3.75 and 5.75. There is 1 hydrogen in each of these environments.

2*1H being split into a hextet and a multiplet severely restricts the isomer possibilities.

The peak at 3.75 is Hextet peak, meaning that there are five adjacent hydrogens. A plausible way this could happen is if the peak is a H-C-O peak with a -CH3 and a CH2 adjacent.

The reason I deduced it's a H-C-O peak and not H-C(CH3CH2OH)-CH=C is because of the multiplet at 5.7.

H-C(CH3CH2OH)-CH=C would likely result in a triplet at 5.7 (-CH=C) instead of this multiplet.

So CH3-CH(OH)-CH2-CH=CH2 'allows' both those 2 single CHs to produce strong multiplets.

I checked the estimated regions of these peaks using a data table and they line up well also.
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thenextchemist
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Thanks so much! I've been struggling for so long!! ARGH
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