Ssitronellal

Citronellal is a naturally occurring organic compound classified as a monoterpene aldehyde, belonging to the broader group of terpenoids. It is a colorless liquid with a fresh, citrusy aroma reminiscent of lemon and rose, which contributes to its widespread use in fragrances and flavorings. Chemically, citronellal has the molecular formula C10H18O and consists of a ten-carbon chain with an aldehyde functional group at one end and a double bond typically located at the third carbon.

The compound is found in various essential oils, particularly those derived from citrus fruits such as lemons, oranges, and bergamot, as well as from plants like citronella grass (*Cymbopogon nardus* and *Cymbopogon winterianus*), geraniums, and lavender. Citronellal is also produced synthetically for industrial applications due to its desirable scent profile and stability.

In the fragrance industry, citronellal serves as a key ingredient in perfumes, soaps, and cosmetics, where it provides a bright, uplifting note. It is also utilized in household cleaning products and air fresheners. Beyond its aromatic properties, citronellal exhibits mild insect-repellent qualities, contributing to its inclusion in mosquito-repellent formulations. However, its effectiveness as a repellent is generally considered modest compared to other compounds like DEET.

From a chemical standpoint, citronellal can undergo various reactions, including oxidation to form citronellic acid and reduction to yield citronellol, another widely used fragrance compound. It is soluble in organic solvents but sparingly soluble in water. Due to its natural occurrence and synthetic accessibility, citronellal is classified as generally recognized as safe (GRAS) by regulatory agencies for use in food and cosmetic applications within specified limits.