The above section of an NMR was taken from a student sample of this experiment. You see while the 2H triplet is still present at around 4.3 ppm, the 2H quartet is gone, replaced by a 3H singlet. As well a 3H triplet at 1.4 ppm also is missing from the NMR. Looking at the procedure for purifying virstatin ethyl ester you see that the ethyl ester is boiled in methanol. It appears that transesterification may occur in this process, resulting in virstatin methyl ester. In light of this statement explain the 3H singlet shown above and the missing 3H triplet. You may draw structures to help in your explanation, in any case make sure the hydrogens you are discussing are UNAMBIGUOUS.

The above section of an NMR was taken from a student sample of this experiment. You see while the 2H triplet is still present at around 4.3 ppm, the 2H quartet is gone, replaced by a 3H singlet. As well a 3H triplet at 1.4 ppm also is missing from the NMR. Looking at the procedure for purifying virstatin ethyl ester you see that the ethyl ester is boiled in methanol. It appears that transesterification may occur in this process, resulting in virstatin methyl ester. In light of this statement explain the 3H singlet shown above and the missing 3H triplet. You may draw structures to help in your explanation, in any case make sure the hydrogens you are discussing are UNAMBIGUOUS.

Organic Chemistry

9th Edition

ISBN:9781305080485

Author:John E. McMurry

Publisher:John E. McMurry

Chapter24: Amines And Heterocycles

Section24.SE: Something Extra

Problem 65AP: Phenacetin, a substance formerly used in over-the-counter headache remedies, has the formula...

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