Krafft degradation

What is Krafft degradation?

The Krafft degradation method involves the conversion of carboxylic acids, particularly those with high molecular weight, into the next lower homologue by subjecting the alkaline earth salt of the acid to dry distillation along with the corresponding acetate. This is followed by the oxidation of the resulting methyl ketone using chromic acid.

Through this process, the original carboxylic acid molecule is shortened by one carbon atom, resulting in the formation of the next lower homologue.

Krafft degradation
Krafft degradation

This method is useful for transforming a higher fatty acid into its next lower homologue. The process involves forming the corresponding methyl ketone through dry distillation of the alkaline earth salt with the corresponding acetate. The resulting methyl ketone can then be oxidized using chromic acid.

Krafft degradation - shortening fatty acid length
Krafft degradation (shortening fatty acid length)


Krafft, F. (1879), Ueber die Laurinsäure und ihre Umwandlung in Undecylsäure. [On lauric acid and its conversion to undecylic acid.] Ber. Dtsch. Chem. Ges., 12: 1664-1668.