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NMR spectroscopy question need help

Ok so... the beginning of this question is fairly easy... you know its an alcohol from the OH group in the infrared spectrum.

Then, you can work out the different integral ratios... that tells you the 0.4 one is ROH and the rest. Have I gone wrong in my PPM notation? Because I can CLEARLY see that the 1.5 PPM one should be an R3CH according to the data sheet... yet the mark scheme answer has no CH in their molecule?? I get very lost once we have to start putting the molecule together... if someone could show me how it's done in a logical manner I would be insanely greatful...
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Original post by pondering-soul
Ok so... the beginning of this question is fairly easy... you know its an alcohol from the OH group in the infrared spectrum.

Then, you can work out the different integral ratios... that tells you the 0.4 one is ROH and the rest. Have I gone wrong in my PPM notation? Because I can CLEARLY see that the 1.5 PPM one should be an R3CH according to the data sheet... yet the mark scheme answer has no CH in their molecule?? I get very lost once we have to start putting the molecule together... if someone could show me how it's done in a logical manner I would be insanely greatful...


With experience you learn to spot what's going on here (sorry).

There is an integration 6 peak, this screams two identical CH3 units.

There is an integration 4 peak, which screams 2x CH2 units.

The int 6 peak is a triplet, which means both of the CH3 units are next to CH2.

Likewise the int 4 peak is a quartet, so both are next to CH3.

They are therefore two identical ethyl groups.

The rest falls into place.
Original post by Pigster
With experience you learn to spot what's going on here (sorry).

There is an integration 6 peak, this screams two identical CH3 units.

There is an integration 4 peak, which screams 2x CH2 units.

The int 6 peak is a triplet, which means both of the CH3 units are next to CH2.

Likewise the int 4 peak is a quartet, so both are next to CH3.

They are therefore two identical ethyl groups.

The rest falls into place.

thank you bro you don't know how much this has helped me I was so confused for a good hour

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