Oximes, Imines, Hydrazones and Azines

5 Imines, Oximes, Hydrazones, and Azines /y Chemical Shifts (d in ppm) 

In aldoximes and ketoximes, the chemical shift difference between syn and anti protons at the a-CH group, A6 = 6gyjj - depends on the dihedral angle, 

Because of the symmetrical electron distribution around the N atom, the quadrupole relaxation of the nitrogen nucleus is so slow that the coupling becomes ob- 

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