Suberic acid monomethyl ester
[CAS# 3946-32-5]

Identification

• Classification: Chemical reagent >> Organic reagent >> Ester >> Methyl ester compound
• Name: Suberic acid monomethyl ester
• Synonyms: 8-methoxy-8-oxooctanoic acid
• Molecular Formula: C₉H₁₆O₄
• Molecular Weight: 188.22
• CAS Registry Number: 3946-32-5
• EC Number: 609-687-7
• SMILES: COC(=O)CCCCCCC(=O)O

Properties

• Density: 1.1±0.1 g/cm³ Calc.^*, 1.047 g/mL (Expl.)
• Melting point: 17 - 19 °C (Expl.)
• Boiling point: 303.9 °C 760 mmHg (Calc.)^*, 343.4 - 344.7 °C (Expl.)
• Flash point: 108.0±16.1 °C (Calc.)^*, 113 °C (Expl.)
• Index of refraction: 1.45 (Calc.)^*, 1.444 (Expl.)

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

Safety Data

• Hazard Symbols: GHS07 Warning
• Risk Statements: H315-H319-H335
• Safety Statements: P261-P264-P264+P265-P271-P280-P302+P352-P304+P340-P305+P351+P338-P319-P321-P332+P317-P337+P317-P362+P364-P403+P233-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Skin irritation	Skin Irrit.	2	H315
Specific target organ toxicity - single exposure	STOT SE	3	H335
Eye irritation	Eye Irrit.	2	H319
Eye irritation	Eye Irrit.	2A	H319

Discovery and Applications

Suberic acid monomethyl ester is a monoester derivative of suberic acid, a saturated eight-carbon dicarboxylic acid. Its structure consists of an eight-carbon linear chain bearing one free carboxylic acid group and one methyl ester group at opposite termini. The molecular formula can be represented as C₉H₁₆O₄. This bifunctional molecule combines the reactivity of both a carboxylic acid and an ester, making it useful as an intermediate in organic synthesis and polymer chemistry.

The preparation of suberic acid monomethyl ester typically involves partial esterification of suberic acid with methanol under controlled acidic conditions to ensure selective conversion of only one carboxyl group to the methyl ester. Reaction parameters such as temperature, catalyst concentration, and molar ratios are adjusted to favor monoester formation over diesterification. Alternatively, selective protection-deprotection strategies can be used to obtain the monoester with high purity.

Suberic acid monomethyl ester serves as a versatile intermediate in the synthesis of polymers, surfactants, and specialty chemicals. Its free carboxylic acid group can undergo typical acid reactions such as amidation or further esterification, while the methyl ester moiety can be hydrolyzed, transesterified, or reduced, providing diverse synthetic pathways. This dual functionality enables the design of asymmetrical molecules and block copolymers with tailored properties.

In polymer chemistry, the monoester is employed as a building block for producing polyesters and polyamides with controlled chain architectures. The presence of both an acid and ester group allows for selective reactivity, which can be exploited in stepwise polymerization processes or in creating functionalized polymer end groups. Polymers derived from suberic acid monomethyl ester exhibit properties influenced by the eight-carbon alkyl spacer, including flexibility, moderate hydrophobicity, and thermal stability.

The compound is also valuable in surface modification and materials science. Its bifunctional nature permits covalent attachment to surfaces or nanoparticles via the acid group, while the ester functionality provides opportunities for further chemical modifications, enabling the development of functional coatings, adhesives, and nanostructured materials.

Physically, suberic acid monomethyl ester is typically a colorless to pale yellow liquid or solid, depending on purity and preparation method. It is moderately soluble in organic solvents such as alcohols, ethers, and chlorinated solvents, while its solubility in water is limited due to its hydrophobic alkyl chain.

Chemical stability is generally good under ambient conditions, but the ester bond can be susceptible to hydrolysis in acidic or basic environments. Proper storage in dry, cool conditions helps maintain compound integrity.

Suberic acid and its derivatives, including the monomethyl ester, can be sourced from renewable feedstocks such as plant oils or via microbial fermentation, aligning with green chemistry and sustainable production goals.

In summary, suberic acid monomethyl ester is a bifunctional molecule combining carboxylic acid and ester groups on an eight-carbon chain, serving as a valuable intermediate in organic synthesis, polymer chemistry, and materials science. Its selective reactivity and structural features enable diverse applications across chemical and industrial fields.

References

2016. Boric Acid Catalyzed Direct Amidation between Amino-Azaarenes and Carboxylic Acids. Synthesis, 48(24).
DOI: 10.1055/s-0036-1588126

2009. Kolbe Electrolysis. Science of Synthesis.
URL: https://science-of-synthesis.thieme.com/app/text/?id=SD-048-00023

2008. Total Syntheses of Phomallenic Acids B and C Utilizing Palladium-Catalyzed Coupling of Propargylic Tosylates with Terminal Alkynes. Synthesis, 2008(6).
DOI: 10.1055/s-2008-1032116