cis-1,2-Cyclopentanedicarboxylic acid
[CAS# 1461-96-7]

Identification

• Classification: Chemical reagent >> Organic reagent >> Fatty acid
• Name: cis-1,2-Cyclopentanedicarboxylic acid
• Molecular Formula: C₇H₁₀O₄
• Molecular Weight: 158.15
• CAS Registry Number: 1461-96-7
• EC Number: 664-400-2
• SMILES: C1C[C@H]([C@H](C1)C(=O)O)C(=O)O

Properties

• Density: 1.4±0.1 g/cm³, Calc.^*
• Melting point: 132-136 ºC (Expl.)140-141 ºC^**
• Index of Refraction: 1.535, Calc.^*
• Boiling Point: 378.6±35.0 ºC (760 mmHg), Calc.^*
• Flash Point: 196.9±22.4 ºC, Calc.^*

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

^** Brenner, Joseph E.; Journal of Organic Chemistry 1961, V26, P22-7.

Safety Data

• Hazard Symbols: GHS07 Warning
• Hazard Statements: H315-H319
• Precautionary Statements: P264-P264+P265-P280-P302+P352-P305+P351+P338-P321-P332+P317-P337+P317-P362+P364

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Eye irritation	Eye Irrit.	2	H319
Skin irritation	Skin Irrit.	2	H315
Acute toxicity	Acute Tox.	4	H332
Acute toxicity	Acute Tox.	4	H302
Acute toxicity	Acute Tox.	4	H312

Discovory and Applicatios

cis-1,2-Cyclopentanedicarboxylic acid is an organic compound with the molecular formula C₇H₁₀O₄. It consists of a five-membered cyclopentane ring bearing two carboxylic acid groups positioned at the 1 and 2 positions in a cis configuration, meaning both carboxyl groups are on the same side of the ring plane. This stereochemistry plays an important role in its physical properties and reactivity. The compound belongs to the family of cycloalkanedicarboxylic acids and is one of the stereoisomers of 1,2-cyclopentanedicarboxylic acid, the other being the trans isomer.

The synthesis of cis-1,2-cyclopentanedicarboxylic acid has been achieved through several classical organic methods, most notably by the oxidation of suitable cyclopentane precursors such as cis-1,2-dimethylcyclopentane or its derivatives using strong oxidizing agents. One well-established synthetic route includes the oxidation of cis-1,2-cyclopentanediol with nitric acid or other oxidants to yield the desired dicarboxylic acid. The stereochemistry of the starting material determines the configuration of the product, and careful control of reaction conditions is required to maintain the cis arrangement of the carboxyl groups.

cis-1,2-Cyclopentanedicarboxylic acid is a valuable intermediate in organic synthesis. Its two closely positioned carboxylic acid groups make it suitable for conversion into anhydrides, esters, and amides. These functional derivatives are often employed in the preparation of fine chemicals, including pharmaceuticals and agrochemicals. The compound's reactivity is influenced by the ring strain and the cis configuration, which affects the spatial orientation of the reactive groups and influences the types of chemical transformations that can be efficiently performed.

In polymer chemistry, cis-1,2-cyclopentanedicarboxylic acid has been used as a monomer or a co-monomer in the synthesis of polyesters and polyamides. The presence of two carboxylic acid groups enables polycondensation reactions with diols or diamines, leading to the formation of linear or branched polymeric materials. Such polymers have been investigated for their mechanical properties, chemical resistance, and potential use in specialty plastics and coatings.

The compound has also been studied in coordination chemistry. The two carboxylic acid groups can act as bidentate ligands, allowing the formation of metal complexes with transition metals such as copper, zinc, and iron. These metal complexes have been examined for their structural characteristics and possible catalytic properties. The rigidity of the cyclopentane ring and the defined cis geometry contribute to the stability and specificity of the coordination complexes.

In analytical and physical chemistry, cis-1,2-cyclopentanedicarboxylic acid has been used as a model compound for investigating intramolecular hydrogen bonding and conformational behavior in cyclic dicarboxylic acids. Spectroscopic techniques such as nuclear magnetic resonance (NMR) spectroscopy and infrared (IR) spectroscopy have been employed to study its structural features. The IR spectrum typically shows two strong absorption bands corresponding to the stretching vibrations of the carboxylic acid groups. NMR spectra display characteristic chemical shifts that confirm the cis configuration.

The compound is generally obtained as a crystalline solid and is soluble in water and polar organic solvents such as methanol and ethanol. It exhibits typical acid-base properties and can form salts with bases, including sodium, potassium, and ammonium hydroxides. These salts have been explored for their potential use in coordination chemistry and in the formulation of certain chemical products.

cis-1,2-Cyclopentanedicarboxylic acid is of interest in chemical research due to its unique combination of stereochemistry, ring structure, and bifunctionality. Its well-documented synthetic accessibility and reactivity make it a useful building block for the development of new materials and chemical entities across a variety of applications.

References

2007. Exchange Reactions with Acetic Anhydride. Science of Synthesis.
DOI: 10.1055/sos-SD-020-00605