n-Eicosane

Synthesis

Pd(OAc)₂ (9.0 mg, 0.040 mmol), PCy₃ (22.4 mg, 0.080 mmol), and K₃PO₄•H₂O (276 mg, 1.20 mmol) were added to a reaction vessel equipped with a stir bar. The vessel was sealed with a diaphragm. The vessel was purged with argon for 15 minutes. Trialkylborane (1.2 mmol; 0.50 M THF solution) and alkyl bromide (1.0 mmol) were added via syringe. The resulting heterogeneous reaction mixture was stirred vigorously at room temperature for 16–24 hours. After the reaction was complete, the mixture was diluted with Et₂O. The mixture was filtered through silica gel using a large amount of washing buffer (Et₂O). The mixture was concentrated. The product was purified by rapid column chromatography to give n-eicosane.

Figure: Synthetic Route of n-Eicosane

Biodegradation

Studies have shown that N-EICOSANE can be degraded by the fungus Trichoderma sp. S019 in both liquid culture and soil, with a degradation rate of up to 77% in liquid culture. The degradation products are likely to be nonanoic acid, n-octadecane, hexadecanoic acid, oleic acid and stearic acid^[1].

Chemical Properties

colourless crystals or wax-like solid

Uses

n-Eicosane is a saturated aliphatic hydrocarbon, which is used to form candles and paraffin waxes with solar energy storage capacity. It is also used in cosmetics, lubricants, plasticizers and in the petrochemical industry. Further, it is useful for special surfactants and in the preparation of certain organic chemicals. In addition to this, it is used as a chromatographic analysis reference material.

Uses

Eicosane is a long chain saturated aliphatic hydrocarbon. Eicosane has a high flashpoint which makes it an inefficient fuel for use in the petrochemical industry. Eicosane is used to form candles and paraffin waxes with solar energy storage capacity.

Definition

ChEBI: Icosane is a straight chain alkane composed of 20 carbon atoms. It has been isolated from the leaves of Agave attenuata. It has a role as a plant metabolite.

Application

n-Eicosane (chemical formula C₂₀H₄₂) is a long-chain alkane characterised by its non-toxicity, lack of chemical corrosiveness and excellent stability. With a melting point of approximately 38°C, which is very close to human body temperature (36.6°C), it is an ideal filling material for the textile industry. Used as a filler in phase-change materials (PCMs), it primarily serves as the core material for microcapsules, utilising the latent heat absorbed or released during the solid-liquid phase transition to regulate temperature. These microcapsules are widely used in the textile, construction and pharmaceutical sectors^[2].

General Description

Colorless crystals or white crystalline solid.

Air & Water Reactions

Insoluble in water.

Reactivity Profile

Saturated aliphatic hydrocarbons, such as N-EICOSANE, may be incompatible with strong oxidizing agents like nitric acid. Charring of the hydrocarbon may occur followed by ignition of unreacted hydrocarbon and other nearby combustibles. In other settings, aliphatic saturated hydrocarbons are mostly unreactive. They are not affected by aqueous solutions of acids, alkalis, most oxidizing agents, and most reducing agents. When heated sufficiently or when ignited in the presence of air, oxygen or strong oxidizing agents, they burn exothermically to produce carbon dioxide and water.

Fire Hazard

N-EICOSANE is combustible.

Purification Methods

Crystallise eicosane from EtOH. [Beilstein 1 IV 563.]

References

[1] Tony Hadibarata, Kazutaka I., Sanro Tachibana. (2007). Biodegradation of n-eicosane by fungi screened from nature. Pakistan Journal of Biological Sciences, 10 11, 1804–1810. https://doi.org/10.3923/pjbs.2007.1804.1810
[2] B. Zgardzińska . (2016). Properties of n-eicosane-filled microcapsules with different morphology. Phase Change Materials studied by positron spectroscopy and complementary methods. Materials Chemistry and Physics, 177, Pages 79-91. https://doi.org/10.1016/j.matchemphys.2016.03.048