Octabenzone
[CAS# 1843-05-6]

Identification

• Classification: Chemical reagent >> Organic reagent >> Aromatic ketone
• Name: Octabenzone
• Synonyms: Ultraviolet Absorber UV-531; 2-Hydroxy-4-n-octoxybenzophenone; 2-Hydroxy-4-n-octyloxybenzophenone; 2'-Hydroxy-4'-n-octyloxybenzophenone; 2-Hydroxy-4-(octyloxy)benzophenone; [2-Hhydroxy-4-(octyloxy)phenyl]phenylmethanone
• Molecular Formula: C₂₁H₂₆O₃
• Molecular Weight: 326.43
• CAS Registry Number: 1843-05-6
• EC Number: 217-421-2
• SMILES: CCCCCCCCOC1=CC(=C(C=C1)C(=O)C2=CC=CC=C2)O

Properties

• Density: 1.1±0.1 g/cm³, Calc.^*, 1.16 g/mL
• Melting point: 47-49 °C
• Index of Refraction: 1.548, Calc.^*
• Boiling Point: 457.9±30.0 °C (760 mmHg), Calc.
• Flash point: 102 °C

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

Safety Data

• Hazard Symbols: GHS07 Warning
• Risk Statements: H317-H412-H413
• Safety Statements: P261-P272-P273-P280-P302+P352-P321-P333+P317-P362+P364-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Skin sensitization	Skin Sens.	1	H317
Chronic hazardous to the aquatic environment	Aquatic Chronic	3	H412
Chronic hazardous to the aquatic environment	Aquatic Chronic	4	H413
Skin sensitization	Skin Sens.	1B	H317
Flammable liquids	Flam. Liq.	3	H226
Chronic hazardous to the aquatic environment	Aquatic Chronic	1	H410
Skin irritation	Skin Irrit.	2	H315
Eye irritation	Eye Irrit.	2	H319

Discovery and Applications

Octabenzone, also known as octabenzone-1, is a synthetic organic compound primarily recognized for its role as a UV absorber and stabilizer in various applications. Its discovery can be traced back to the mid-20th century when researchers began exploring compounds capable of providing protection against harmful ultraviolet (UV) radiation. This compound is characterized by its unique molecular structure, consisting of multiple benzene rings that contribute to its effectiveness in absorbing UV light, making it a valuable additive in a wide range of products.

The synthesis of octabenzone typically involves multi-step chemical reactions that incorporate benzene derivatives. Its structure allows it to absorb UV light across a broad spectrum, effectively dissipating the energy before it can cause damage to materials or biological systems. This property has led to its widespread use in various industries, particularly in plastics, coatings, and personal care products.

One of the primary applications of octabenzone is in the formulation of plastics, where it serves as a UV stabilizer. Plastics are often susceptible to degradation when exposed to UV radiation, leading to discoloration, brittleness, and loss of mechanical properties. By incorporating octabenzone into plastic formulations, manufacturers can enhance the longevity and durability of their products, ensuring they maintain their structural integrity and appearance over time. This application is particularly important for outdoor products, such as furniture, automotive components, and construction materials, which are frequently exposed to sunlight.

In addition to its use in plastics, octabenzone is also utilized in coatings and paints. UV radiation can significantly impact the performance and aesthetics of coatings, leading to fading and surface deterioration. The inclusion of octabenzone in paint formulations helps to mitigate these effects, providing better protection against the harmful effects of sunlight. This is especially valuable for exterior paints, where prolonged exposure to UV light can shorten the lifespan of the coating.

Another notable application of octabenzone is in the cosmetics and personal care industry. It is commonly used as a UV filter in sunscreen formulations to protect the skin from harmful UV radiation. By absorbing UV light, octabenzone helps prevent sunburn and reduces the risk of skin cancer and premature aging caused by sun exposure. Its effectiveness in providing broad-spectrum UV protection has made it a popular choice for formulators of sun care products.

Despite its beneficial applications, the use of octabenzone has raised concerns regarding its environmental impact and potential toxicity. Research has indicated that some UV absorbers, including octabenzone, can leach into water bodies, potentially affecting aquatic ecosystems. Consequently, regulatory agencies have begun to scrutinize the use of octabenzone in certain applications, particularly in cosmetics. As a result, researchers are actively exploring alternative UV absorbers that are safer for both human health and the environment.

In conclusion, octabenzone is a significant chemical compound with diverse applications across multiple industries, particularly as a UV absorber in plastics, coatings, and personal care products. Its discovery has played a crucial role in enhancing the durability and effectiveness of products exposed to sunlight. While its applications continue to be valuable, ongoing research is necessary to address environmental and health concerns associated with its use, leading to the development of safer alternatives in the future.

References

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DOI: 10.1016/j.celrep.2021.109040

2020. Therapeutic candidates for the Zika virus identified by a high-throughput screen for Zika protease inhibitors. Proceedings of the National Academy of Sciences of the United States of America.
DOI: 10.1073/pnas.2005463117