Chemical Properties
Clear yellow viscous liquid
Uses
antineoplastic, convulsant
Uses
Solvent for solid sunscreens. UV absorber for plastics and paints.
General Description
Yellow viscous liquid. Insoluble in water.
Reactivity Profile
2-ETHYLHEXYL-2-CYANO-3,3-DIPHENYLACRYLATE(6197-30-4) is an ester derivative. Esters react with acids to liberate heat along with alcohols and acids. Strong oxidizing acids may cause a vigorous reaction that is sufficiently exothermic to ignite the reaction products. Heat is also generated by the interaction of esters with caustic solutions. Flammable hydrogen is generated by mixing esters with alkali metals and hydrides.
Air & Water Reactions
Insoluble in water.
Fire Hazard
Flash point data for this chemical are not available. 2-ETHYLHEXYL-2-CYANO-3,3-DIPHENYLACRYLATE is probably combustible.
Description
Octocrylene (OCT) is a viscous, clear, colorlesss oi introduced in commercial sunscreens and anti-ageing creams about 15 years ago. It is the 2-ethylhexyl ester of 2-cyano-3,3-diphenylacrylic acid, with the extended conjugation of the acid portion that absorbs UVB and short-wave UVA (ultraviolet) rays, with wavelengths from 280 to 320 nm, which promote tanning but also contribute to the onset of sunburn and skin cancer. It is used in various body care products, in concentrations up to 10%, to provide an adequate sun-protection factor or to protect the body care formulations themselves from UV radiation[1].
Application
octocrylene is a uVB sunscreen with strong water-resistant properties and a rather broad-band absorption range. It exhibits good photostability, and is being evaluated by many companies as an effective SPF booster and waterproofing enhancer. This is an expensive ingredient with an approved usage level of 7 to 10 percent in both the united States and the european union. Although gaining in popularity among formulators, its cost and usage level can limit use. In addition, some studies are indicating it may cause allergic reactions in skin with a history of photoallergy.
Definition
ChEBI: Octocrylene is a diarylmethane. It is an ester formed by the condensation of a diphenylcyanoacrylate with 2-ethylhexanol, used in sunscreens and cosmetics.
benefits
Octocrylene is a compound often used as an additive in sun screen, and is thought to have skin moisturizing effects because of its emollient properties. What makes this chemical such a popular additive to sun block, is its ability to neutralize UV radiation dissipated by sunlight, and to minimize skin damage from prolonged sun exposure. Octocrylene protects the skin from the harmful effects of the sun and premature skin aging. It helps prevent the risk of skin cancer. This filter mainly absorbs UVB rays, and shorter UVA rays, which are responsible for aging but also for skin cancer.
Flammability and Explosibility
Nonflammable
Side effects
Some people are concerned about the body’s ability to absorb octocrylene, which can present in the blood, urine, and breast milk. It may promote the production of free radicals, which can damage DNA, potentially increasing the risk of melanoma. However, further research is necessary.
People with sensitive skin or skin conditions, such as eczema, may prefer to avoid products containing octocrylene. Alternatively, a person can perform a patch test before using a product containing octocrylene for the first time. The patch test should indicate if an individual is allergic or sensitive to an ingredient in the product.
The Food and Drug Administration (FDA) evaluated the safety of octocrylene for use in sunscreen products and found that concentrations of up to 10% are safe.
The European Scientific Committee on Consumer Safety (SCCS) also stated that octocrylene is safe in products containing concentrations of no more than 10%.
Berardesca, E.,et al.(2019). Review of the safety of octocrylene used as an ultraviolet filter in cosmetics.
https://onlinelibrary.wiley.com/doi/full/10.1111/jdv.15945
Safety Profile
Low toxicity by ingestion. Whenheated to decomposition it emits toxic vapors of NOx.
Synthesis
To a 1000 mL four-necked round-bottomed flask equipped with a mechanical stirrer, thermometer, and condenser tube, 2-ethylhexyl cyanoacetate (347 g, 1.76 mol), benzophenone (200 g, 1.1 mol), recovered acetic acid (168.3 g with 2% water, 2.75 mol), and ammonium acetate (3 g, 0.4 mol) were added sequentially. Stirring was turned on and the reaction mixture was heated to 85-90 °C. The acetic acid/water mixture was distilled azeotropically under reduced pressure at 400-420 mmHg for 16 h until gas chromatographic analysis showed no further decrease in benzophenone concentration in the reaction mixture. The loss of acetic acid was regulated by making up the recovered acetic acid during the process. Subsequently, the remaining acetic acid was recovered under reduced pressure at 30-60 mmHg. The reaction mixture was analyzed by HPLC and showed a BPCA content of 0.19%. The crude product was cooled, washed twice with 300 g of water and then distilled to give a light yellow viscous liquid (303 g, 76.3% yield) with a purity of 99.48% as analyzed by gas chromatography.
References
[1] Antonio Medici. “Octocrylene: From Sunscreens to the Degradation Pathway during Chlorination Processes: Formation of Byproducts and Their Ecotoxicity Assessment.” Molecules (2022).
