(S)-(−)-Citronellic Acid: Properties, Uses & FAQs

(S)-(−)-Citronellic acid is a chiral, enantiomerically enriched monoterpene-derived carboxylic acid widely used as a building block in asymmetric synthesis and as a chiral auxiliary or precursor in the preparation of enantiomerically pure natural products and pharmaceuticals.

Chemical Name

(S)-(−)-3,7-Dimethyl-6-octenoic acid

Aladdin SKU

S472338

Optical Activity

(−) enantiomer, S-configuration

Compound Class

Monoterpene carboxylic acid (chiral)

Reference Standard

Sigma catalog No. 364428 (cross-reference)

Molecular Formula

C₁₀H₁₈O₂

Molecular Weight

170.25 g/mol

What Is (S)-(−)-Citronellic Acid?

(S)-(−)-Citronellic acid, systematically named (S)-(−)-3,7-dimethyl-6-octenoic acid, is a chiral monoterpene carboxylic acid bearing a stereocenter at the C-3 position. It is the S-configured enantiomer of citronellic acid, derived biosynthetically from the monoterpene citronellol. The compound is a colorless to pale-yellow liquid or low-melting solid with a mild terpene-like odor. Its molecular formula is C₁₀H₁₈O₂ and molecular weight is 170.25 g/mol. The defined stereocentre makes this compound valuable in enantioselective chemistry, distinguishing it from the racemic mixture or the (R)-(+) enantiomer.

Applications in Research and Synthesis

(S)-(−)-Citronellic acid serves as a versatile chiral building block in organic synthesis. Key applications include:

• Asymmetric synthesis: The defined S stereocentre allows its use as a starting material or intermediate in the total synthesis of enantiomerically pure natural products, including terpenoid and macrolide targets.
• Pharmaceutical intermediates: Its chiral carboxylic acid functionality can be coupled, reduced, or functionalized to generate enantiopure pharmaceutical intermediates.
• Chiral pool chemistry: As a naturally derived chiral acid, it is a member of the chiral pool, enabling researchers to introduce chirality without requiring separate asymmetric induction steps.
• Fragrance and flavor research: Citronellic acid and its derivatives are studied for their sensory properties and biotransformation pathways in flavor science.

Researchers working on enantioselective methodology, terpene biosynthesis, or chiral ligand development commonly employ this reagent.

Handling, Storage and Safety

Proper handling and storage of (S)-(−)-Citronellic acid (SKU S472338) are essential to preserve enantiopurity and reagent integrity:

• Storage temperature: Store at room temperature (15–25 °C) in a cool, dry, well-ventilated location, away from direct light and moisture. Refrigeration (2–8 °C) may be used for extended storage.
• Container: Keep tightly sealed under an inert atmosphere (nitrogen or argon) to prevent oxidation of the olefinic double bond and moisture uptake.
• Personal protection: Use standard laboratory PPE including gloves, safety glasses, and lab coat. Avoid inhalation of vapors.
• Disposal: Dispose of according to local regulations for organic chemical waste.

Always consult the Safety Data Sheet (SDS) provided with the product before use.

Purity, Grade and Quality Specifications

For chiral reagents such as (S)-(−)-Citronellic acid, both chemical purity and enantiomeric excess (ee) are critical quality parameters:

• Chemical purity: Typically assessed by GC or HPLC; high-purity grades suitable for synthesis are expected to be ≥95% chemically pure (specific lot values are provided on the certificate of analysis).
• Enantiomeric excess (ee): The S-enantiomeric excess should be confirmed by chiral GC, chiral HPLC, or polarimetry. Researchers should verify the ee value from the certificate of analysis for each lot before use in enantioselective reactions.
• Optical rotation: The negative sign of rotation ([α]D negative) confirms the S-configuration; the specific magnitude should be confirmed against the CoA.

Aladdin Scientific provides a certificate of analysis (CoA) with each lot. Customers are encouraged to request the CoA to verify purity and ee prior to use.

Ordering and Availability

(S)-(−)-Citronellic acid is available from Aladdin Scientific under SKU S472338. To order:

• Search for SKU S472338 directly on the Aladdin Scientific website or catalog.
• Multiple pack sizes may be available; contact Aladdin customer service for bulk or custom quantities.
• This product is cross-referenced with Sigma catalog No. 364428 for researcher convenience.
• For institutional or high-volume procurement, please contact the Aladdin sales team for pricing and availability.

For questions about shipping conditions, lead times, or export documentation, please contact Aladdin Scientific customer support.

Frequently asked questions

What is the CAS number of (S)-(−)-Citronellic acid?

The CAS number for (S)-(−)-Citronellic acid is commonly cited as 18951-80-9 for the S-enantiomer. Researchers should confirm the CAS number against the product label and certificate of analysis upon receipt, as CAS registry entries for enantiomers can vary by supplier.

How do I confirm the enantiomeric excess (ee) of (S)-(−)-Citronellic acid before using it in an asymmetric reaction?

Enantiomeric excess can be determined by chiral-phase GC or chiral-phase HPLC using an appropriate chiral stationary phase column, or by measuring the specific optical rotation ([α]D) and comparing it to a literature or CoA reference value. Aladdin Scientific provides a certificate of analysis for each lot; always request and review the CoA before committing material to a sensitive asymmetric synthesis.

What are typical applications of (S)-(−)-Citronellic acid in organic synthesis?

(S)-(−)-Citronellic acid is primarily used as a chiral pool building block in the total synthesis of terpenoid natural products and pharmaceutical intermediates. Its carboxylic acid group can be converted to esters, amides, aldehydes, or alcohols, while the stereocenter is carried through synthetic sequences to deliver enantioenriched products without additional asymmetric induction steps.

How should (S)-(−)-Citronellic acid be stored to prevent degradation?

Store the compound in a tightly sealed container under an inert atmosphere (nitrogen or argon) at room temperature (15–25 °C) or under refrigeration (2–8 °C) for longer-term storage, in a cool, dry location away from light. The olefinic double bond in the side chain is susceptible to oxidation, so minimizing exposure to air and light is important for maintaining product quality.

Is (S)-(−)-Citronellic acid the same as the product listed under Sigma catalog No. 364428?

Sigma catalog No. 364428 is used as a cross-reference identifier for (S)-(−)-Citronellic acid, and the Aladdin Scientific product S472338 corresponds to this compound. Researchers switching suppliers should verify purity, ee, and specifications via the certificate of analysis for each supplier's lot to ensure suitability for their specific application.

References

1. Sigma-Aldrich (Merck KGaA). (S)-(−)-Citronellic acid, catalog No. 364428, product page. Accessed via sigmaaldrich.com.
2. March, J. Advanced Organic Chemistry: Reactions, Mechanisms, and Structure. 4th ed. Wiley, 1992. (General reference for carboxylic acid reactivity and chiral pool strategies.)
3. Clayden, J.; Greeves, N.; Warren, S. Organic Chemistry. 2nd ed. Oxford University Press, 2012. (Textbook-level reference for chiral building blocks and asymmetric synthesis.)

Products are supplied for research and development use only. Not for use in humans, animals, diagnosis, or therapy.