For a study I had to record the 1H NMR of Propargyl bromide in D2O where it is barely soluble. The spectra that I got had the peaks of methylene proton and terminal alkyne proton at d=3.87 (d, J=2.4 Hz, 2H) and 1.96 (br, 1H) respectively. Since the propargyl bromide is a 80% solution in toluene, stabilized with 0.3 MgO, I also could account for the singlet at d=2.2 for 3H and multiplet at 7.15 for 5H (integration is done considering toluene peaks only).
The spectrum of propargyl bromide had the following peaks i could not account for
d= 6.85 (m, 1.16 H), 3.25 (br, 0.46 H), 2.79 (t, J=2.4 Hz, 0.5 H) [integration with respect to alkyne proton of propargyl bromide]
Could the extra peaks be due to the hydrolysis of propargyl bromide to propargyl alcohol? If yes, can the broad peak at 3.25 be attributed to -OH (spectrum recorded in D2O) of the propargyl alcohol?
You can test your hydrolysis hypothesis by recording the 1H NMR at time zero and after a period of time at different temperatures.
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