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NMR spectra of cyclopentanone Watch

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    http://www.muhlenberg.edu/depts/chem...opentanone.htm

    Could someone help me rationalise this?

    I see that there are two kinds of protons in the molecule. The ones adjacent to the ketone group (which are shifted from the conventional value of 1.3 ppm for CH2 to around 2.1 ppm, in agreement with the rule that you add 1 ppm to the value for a carbonyl). Then there are the protons that are beta to the carbonyl. They are chemically different.

    Are we talking about two single peaks or a doublet? Also, what would the intensity be here? I am guessing each peak is 2 times that of a normal CH2 peak since there will be 4 protons in each chemical environment.

    Any help is appreciated.
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    That is not a spectrum of cyclopentanone - its a computer guess of what it would look like. The H-NMR would have two roofed triplets in that region, the one closer to the ketone will have the higher ppm. The integrations will be the same.
 
 
 
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