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# Ephedrine $^1$HNMR: Peak at 2.76 ppm

ORGO1-CMY19Y

Shown below is the $^1$HNMR (1R, 2S)-ephedrine spectrum in ${D}_{2}O$. Maleic acid was added as an internal standard. The structure of maleic acid is shown on the bottom left, while that of (1R, 2S)-ephedrine is shown on the bottom right, and its hydrogens are labeled with lower case letters.

Determine the identity of the singlet at 2.76 ppm by matching it with the hydrogens labeled with lower case letters.

A

a

B

b

C

c

D

d

E

e

F

f

G

g