Cyclohexanone oxime explained

Cyclohexanone oxime is an organic compound containing the functional group oxime. This colorless solid is an important intermediate in the production of nylon 6, a widely used polymer.

Preparation

Cyclohexanone oxime can be prepared from the condensation reaction between cyclohexanone and hydroxylamine:[1]

C5H10CO + H2NOH → C5H10C=NOH + H2O

Alternatively, another industrial route involves the reaction of cyclohexane with nitrosyl chloride, which is a free radical reaction. This method is advantageous as cyclohexane is much cheaper than cyclohexanone.

Reactions

The most famous and commercially important reaction of cyclohexanone oxime is Beckmann rearrangement yielding ε-caprolactam:

This reaction is catalyzed by sulfuric acid,[1] but industrial scale reactions use solid acids.[2]

Typical of oximes, the compound can be reduced by sodium amalgam to produce cyclohexylamine.[3] It can also be hydrolyzed with acetic acid to give back cyclohexanone.

Notes and References

  1. J. C. Eck and C. S. Marvel "ε-Benzoylaminocaproic Acid" Org. Synth. 1939, volume 19, pp. 20.
  2. Corma, Avelino; Garcia, Hermenegildo "Organic reactions catalyzed over solid acids" Catalysis Today 1997, volume 38, pp. 257-308.
  3. W. H. Lycan, S. V. Puntambeker, and C. S. Marvel "n-Heptylamine" Org. Synth. 1931, volume 11, pp. 58.