The 1H NMR for a dipeptide recorded in D20is shown below.(i) Explain what has happened to the H-atoms attached to the N atoms.(ii) Explain the spectra. Note the signals for HAand HA'are subject to a second order effect.H^H*40 Hz0.1 ppm'N-DN HaL-Ala-Gly(iii) predict which direction the signal for the Hon the alpha-C will move in the 1H NMR ongoing from low to high ph and explain whythis leads to a change in chemical shift.

When molecules are placed in a strong magnetic field, the nuclei of some atoms will begin to behave…

Answered: The 1H NMR for a dipeptide recorded in…

The 1H NMR for a dipeptide recorded in D20 is shown below. (i) Explain what has happened to the H- atoms attached to the N atoms.

Organic Chemistry

9th Edition

ISBN:9781305080485

Author:John E. McMurry

Publisher:John E. McMurry

Chapter26: Biomolecules: Amino Acids, Peptides, And Proteins

Section26.SE: Something Extra

Problem 28MP

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Mass Spectrometry

This process is an instrumental method in which a sample is changed to fast moving positive ions by electron bombardment. The charged particles vary due to their different mass to charge ratio and are estimated with the help of this difference. It is also called mass spectroscopy.

Question

The 1H NMR for a dipeptide recorded in D20
is shown below.
(i) Explain what has happened to the H-
atoms attached to the N atoms.
(ii) Explain the spectra. Note the signals for HA
and HA'are subject to a second order effect.
H^H*
40 Hz
0.1 ppm
'N-
DN Ha
L-Ala-Gly
(iii) predict which direction the signal for the H
on the alpha-C will move in the 1H NMR on
going from low to high ph and explain why
this leads to a change in chemical shift.

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