Hofmann's Rule implies that steric effects have the greatest influence
on the outcome of the Hofmann
or similar eliminations. The loss of the β-hydrogen occurs preferably
from the most unhindered (least substituted) position [-CH3 >
-CH2-R > -CH(R2)]. The product alkene with fewer
substitutents will predominate.
Ester Pyrolysis also obeys this preference, and the Hofmann Rule is generally followed whenever a reaction passes through a cyclic transition state.
Hofmann's Rule is valid for all intramolecular eliminations and for the Hofmann Elimination. Most bimolecular eliminations will follow Saytzeff's Rule.