Question

" Below is a H NMR spectrum of trimyristin (in CDC) (no integrations are shown). On the structure of trimyristin below indicate the hydrogens responsible for the signals: (0.9 points) a) Circle and label with A: all the hydrogens that are responsible for the group of signals from 4.0 10 5.3 ppm do not consider signal splitting only consider information from chemical shift). b) Put in a box and label with B: all the hydrogens that are responsible for the multiplet at 2.25 ppm (do not consider signal splitting only consider information from chemical shift). c) Put in a box and label with C: all the hydrogens that are responsible for the triplet at 0.85 ppm (consider both signal splitting and information from chemical shift). HC-0 + Acto (ppm) (sper) pen)

Answer 1

} All by Al hydrogens that are responsible for the group of from 4.0 to 5.3 ppm. he group of signails Here we have on are highly We have only protons which is attached wilt oxygen are deshielded & which gives signal hom 4.0 to 5.3 ppm. only P > All hydrogens that are responsible for the mw Hplet at 2.25 ppm. Normal -CH2 protons doesn't shows signal at 2.25 ppm but it ng group is attached with carbonyl (- -) group can show's signal 2.25 ppm. But the - CH2 group attached with carbonyl shows Splitting as triplet and not a multiplet. But there, they clearly said that do not consider splitting. So according to chemical shift, the protons are -CH2 protons attached with carbonyl. a ed with cha group All the hydrogens that are responsible for the triplet at 0.85 The signal is for normal protons which is attached with cho as it split as triplet ho this is signal for -CH3 protons.

HC -o HC-o -cha HC-0