Introduction
The dipole moments listed below are derived from the table of
→ dipole moments.
Since there is a significant difference between alkyl (methyl- , ethyl-) and aryl (phenyl-) derivatives
they are listed separately. In the aryl derivatives it is possible to assign a direction to the dipoles
based on the size of the dipole of
p-derivatives. Negative values indicate that the substituent
donates electrons,
i. e. the direction of the dipole moment is from the substituent toward the ring.
The difference between the alkyl and aryl derivatives is due electron donation by resonance from substituents
with free electron pairs to the aryl ring.
