Microwave assisted reactions in Water
Hofmann elimination reaction
Sometimes referred to as hafmann Degradation. This elimination reaction of alkyl trimethyl amines proceeds with anti seterochemistry and is generally sutable for producing alkenes with one or two substituents. The reaction follows the Hafmann Rule.
Mechanism of the Hofmann Elimination
Hofmann's Rule
Hofmann's Rule implies that steric effects have the greatest influence on the outcome of the hafmann or similar eliminations. The loss of the B-hydrogen occurs preferably from the most unhindered (least suitable) position ( -CH3 > -CH2-R > CH(R2)). The product alkene with fewer substituents will predominate.
Hofmann's rule is valid for all intermolecular eliminations and for the Hofmann eliminations. Most bimolecular eliminations will follow saytzeeff's Rule.
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