sitronellal

Sitronellal is an acyclic monoterpene aldehyde. It is a key component of the essential oils of various plants, most notably citronella oil, from which it derives its name. It is also found in plants like lemon eucalyptus and *Litsea cubeba*. Sitronellal is characterized by its pleasant, lemony odor, making it a valuable ingredient in perfumery and aromatherapy.

Chemically, sitronellal exists as two stereoisomers: (R)-sitronellal and (S)-sitronellal. The natural form is predominantly (R)-sitronellal. Its molecular formula is C10H18O. It is a colorless to pale yellow liquid.

In addition to its fragrance properties, sitronellal is recognized for its insect-repelling qualities, particularly against mosquitoes. This repellent effect is the basis for the widespread use of citronella-based products for outdoor activities. Sitronellal can be chemically converted into other compounds, such as citronellol, which is another important fragrance ingredient. Its synthesis and extraction from natural sources are common industrial practices.