84
Please keep in mind:
The coupling constant J is - in contrast to the chemical shift of a resonance signal - not dependent on the external magnetic field of the spectrometer, but rather on the magnetic fields of the neighboring nucleii.Example: For the methyl protons in (CH3)2CH-O-CH(CH3)2the following coupling constants have been determined at different fields:
| JCH3,CH | (at n0 = 250 MHz) = 6.1 Hz | ||
| (at n0 = 600 MHz) = 6.1 Hz |
Draw this doublet (d
= 1.05 ppm) as it would appear in a spectrum with n0 = 100
MHz. Use the following d
axis!
Compare your spectrum with the doublets on page 81! Then continue to page 88! |
