Piperic acid

Preparation

Piperic acid can be prepared from the commercially available alkaloid piperine, a cyclic amide containing a piperidine group, by reacting it with a hydroxide such as potassium hydroxide, then acidifying the formed piperate salt with hydrochloric acid or another acid. The toxic compound piperidine is given off during the base-hydrolysis of piperine and as-such, safety precautions should be taken.

:[[Image:Piperic acid from piperine.jpg|Piperic acid from [[piperine]]]]

Reactions

Reaction of piperic acid with strong oxidizers such as potassium permanganate or ozone, or a halogen such as bromine followed by sodium hydroxide causes oxidative cleavage of the double-bonds, yielding piperonal and piperonylic acid. Piperonal has many uses in industry and is itself a precursor to a good subsection of other chemicals. On reduction with sodium amalgam piperic acid forms α- and β-dihydropiperic acid, C12H12O4, and the latter can take up two further atoms of hydrogen to produce tetrahydropiperic acid.

References

References

1. Paul M. Dewick.. (2009). "Medicinal natural products : a biosynthetic approach". A John Wiley & Sons.
2. E. Gildemeister. "The Volatile Oils".
3. "Preparation process for piperonal".