PINACOLONE
3,3-dimethyl-2-butanone (C6H12O)
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C-1

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NMR 1H APPROXIMATION OF
3,3-dimethyl-2-butanone


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Carbon-3 is bound to 3 adjacent methyl groups. As a result, the protons attached to each adjacent carbon are identical. This results in a singlet; protons on adjacent carbons do not couple:
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There is no adjacent proton on carbon 3, so there is only a single peak. The absorbency is approximately 1.1 ppm which is consistent with the general range methyl groups would fall when bound to a carbon lacking any deshielding atoms – 0.9-1.5 ppm.
Carbon-1 had an absorbency of approximately 2.2 ppm. Protons adjacent to ketones tend to absorb at 2-2.5 ppm. This proton also yielded a single peak because the only atom adjacent to C-1 is C-2 which lacks any protons.