A ¹H NMR spectrum contains a quartet at 4.1 ppm integrating to 2H and triplet at 0.9 ppm integrating to 3H, among other signals. What fragment is likely part of this molecule?

The ¹H NMR spectrum of 2-propen-1-ol is shown here. Indicate the protons in the molecule that are responsible for each of the signals in the spectrum.

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Draw the approximate positions that the following compound might show in its 1H NMR absorptions?

Draw the approximate positions that the following compound might show in its 1H NMR absorptions?

Draw the expected NMR spectrum of methyl propionate, and point out how it differs from the spectrum of ethyl acetate.

Each of these four structures has molecular formula C₄H₈O₂. Match the structure with its characteristic proton NMR signals. (Not all of the signals are listed in each case.)

(a) sharp 1H singlet at δ8.0 and 2H triplet at δ4.0

(b) sharp 3H singlet at δ2.0 and 2H quartet at δ4.1

(c) sharp 3H singlet at δ3.7 and 2H quartet at δ2.3

(d) broad 1H singlet at δ11.5 and 2H triplet at δ2.3

Tell precisely how you would use the proton NMR spectra to distinguish between the following pairs of compounds.

(b)