alpha-Ionone
[CAS# 127-41-3]

Identification

• Classification: Flavors and spices >> Synthetic spice >> Ketone fragrance >> Decenone
• Name: alpha-Ionone
• Synonyms: 4-(2,6,6-Trimethyl-2-cyclohexen-1-yl)-3-buten-2-one
• Molecular Formula: C₁₃H₂₀O
• Molecular Weight: 192.30
• CAS Registry Number: 127-41-3
• EC Number: 204-841-6
• FEMA: 2594
• SMILES: CC1=CCCC(C1/C=C/C(=O)C)(C)C

Properties

• Density: 0.9±0.1 g/cm³, Calc.^*, 0.931 g/mL (Expl.)
• Index of Refraction: 1.512, Calc.^*, 1.498 (Expl.)
• Boiling Point: 257.6 ºC (760 mmHg), Calc.^*, 259 � 263 ºC (Expl.)
• Flash Point: 104.4 ºC, Calc.^*, 117 ºC (Expl.)

^* Calculated using Advanced Chemistry Development (ACD/Labs) Software.

Safety Data

• Hazard Symbols: GHS07;GHS08;GHS09 Danger
• Hazard Statements: H302-H350-H411
• Precautionary Statements: P201-P273-P301+P312+P330-P308+P313-P391-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Chronic hazardous to the aquatic environment	Aquatic Chronic	3	H412
Respiratory sensitization	Resp. Sens.	1	H334
Chronic hazardous to the aquatic environment	Aquatic Chronic	2	H411
Skin sensitization	Skin Sens.	1	H317
Chronic hazardous to the aquatic environment	Aquatic Chronic	1	H411

• Transport Information: UN 3082

Discovory and Applicatios

Alpha-ionone is a chemical compound that is widely known for its distinct aroma and its significant role in the fragrance industry. It is a type of ionone, a group of organic compounds that are derived from carotenoids. Alpha-ionone has a pleasant floral, woody, and violet-like odor and is often used in the production of perfumes, cosmetics, and as a flavoring agent. The compound is found naturally in a variety of plants, including violets and certain fruits, contributing to its characteristic scent.

Alpha-ionone was first identified in the 19th century, when researchers began investigating the chemical composition of essential oils from flowers like violets. The molecule was isolated as part of studies into the volatile compounds that contribute to the scent of these flowers. As with other members of the ionone family, the structure of alpha-ionone is based on the terpenoid backbone, specifically derived from the degradation of carotenoids, which are pigments found in plants. Its molecular structure consists of a bicyclic structure with a carbonyl group and a methyl group, contributing to its distinctive aroma.

The primary application of alpha-ionone is in the fragrance industry, where it is used as a key ingredient in a variety of perfumes and scented products. It is valued for its complex, floral fragrance, which resembles the scent of violets. As such, it is often included in floral or powdery perfume compositions. Alpha-ionone is also used in the production of cosmetics, including lotions, creams, and shampoos, where its pleasant fragrance enhances the overall sensory experience of the products.

In addition to its use in fragrances, alpha-ionone is employed as a flavoring agent in food products. It is used to impart a subtle violet-like flavor to foods, although its application in food is less common than in the fragrance industry. Despite being used in small quantities, alpha-ionone contributes to the overall flavor profile of some confectioneries and beverages.

Beyond its role in fragrances and flavors, alpha-ionone has been studied for its potential therapeutic properties, particularly in relation to its effects on the central nervous system. Some research has suggested that the compound might have mild calming or sedative effects, which could be attributed to its pleasant aroma. However, further studies are needed to fully understand its potential pharmacological benefits.

Alpha-ionone is synthesized commercially by the oxidation of beta-ionone, a closely related compound. It can also be obtained through various synthetic routes involving the use of natural plant sources. Its availability and versatility make it a widely used compound in industries ranging from perfumery to food production.

In conclusion, alpha-ionone is a well-established compound that plays a significant role in the fragrance and flavor industries. Its distinct violet-like odor makes it a popular ingredient in perfumes, cosmetics, and some food products. While primarily used for its sensory properties, alpha-ionone's potential pharmacological applications continue to be explored in scientific research.

References

Vare, T. B., Joshi, R. S. and Giri, A. P., 2024. Aroma Alchemy: Uridine diphosphate-dependent glycosyltransferases mediated regulation of fruit aroma and flavor biosynthesis. Phytochemistry Reviews.
DOI: 10.1007/s11101-024-10049-7

Majumder, S., Ghosh, A. and Bhattacharya, M., 2024. GC�MS analysis underpins ethnomedicinal properties of Rhododendron flower brews from Singalila Himalaya highlighting the anticipated biosynthesis pathways of the bioactives. Discover Food, 4, 171.
DOI: 10.1007/s44187-024-00168-7

van der Schaft, P. H., 2007. Chemical Conversions of Natural Precursors. Flavours and Fragrances, 285.
DOI: 10.1007/978-3-540-49339-6_13