4-methoxyphenol

Synthesis

4-Methoxyphenol was synthesised according to Oxidation with H2O2 and a Diselenide catalyst.p-Anisaldehyde (50 mmol) is dissolved in CH2Cl2 (100mL) and (o-NO2PhSe)2 (2 mmol) and 30% H2O2 (13mL, 128 mmol) are added. The mixture is stirred magnetically at room temperature (water bath) for 30 minutes. Insoluble catalyst is removed by filtration and washed with CH2Cl2 (20mL) and water (20mL). It can be reused after drying. To the filtrate and washings, water (100mL) is added, and the layers are separated after shaking. The organic layer is washed subsequently with 10% NaHSO3 (100mL), 10% Na2CO3 (100mL), water (100mL) and dried over Na2SO4. 4-methoxyphenol is obtained by alkaline hydrolysis of the residue. Yield: 93%.

Indications

Mequinol (4-hydroxyanisole) is a substrate of the enzyme tyrosinase and acts as a competitive inhibitor of melanogenesis.

Synthesis Reference(s)

The Journal of Organic Chemistry, 42, p. 1479, 1977 DOI: 10.1021/jo00428a054Synthesis, p. 751, 1983 DOI: 10.1055/s-1983-30501Tetrahedron Letters, 34, p. 7667, 1993 DOI: 10.1016/S0040-4039(00)61534-4

Air & Water Reactions

Sensitive to moisture. Water soluble.

Reactivity Profile

4-Methoxyphenol can react with oxidizing materials.

Hazard

Eye irritant and skin damage.

Health Hazard

4-Methoxyphenol is expected to cause liver and renal toxicity with narcosis, but only at high levels of exposure.

Flammability and Explosibility

Nonflammable

Safety Profile

Poison by intraperitoneal route. A skin irritant. When heated to decomposition it emits acrid smoke and fumes. See also ETHERS.

Shipping

UN3335 Aviation regulated solid, n.o.s., Hazard class: 9; Labels: 9-Miscellaneous hazardous material, Technical Name Required.

Purification Methods

Crystallise 4-methoxyphenol from *benzene, pet ether or H2O, and dry it under vacuum over P2O5 at room temperature. Sublime it in vacuo. [Wolfenden et al. J Am Chem Soc 109 463 1987, Beilstein 6 IV 5717.]

Chemical Composition and Structure

Mequinol, also known as 4-methoxyphenol, has the molecular formula C7H8O2. It consists of a phenolic ring with a methoxy group (-OCH3) attached to the aromatic ring at the para position.

Categories and Type

Mequinol is categorized as a phenolic compound.^[1]

Medical Uses

Mequinol has been incorporated into wound dressing materials due to its anti-inflammatory and antioxidant properties. It has shown potential in promoting wound healing, particularly in diabetic wounds.^[2]

Cosmetic Uses

Mequinol is used in skincare products for its ability to inhibit melanogenesis and treat hyperpigmentation.

Chemical Synthesis

Mequinol is utilized as an intermediate in the synthesis of various organic compounds, including polymerization inhibitors, antioxidants for foods and cosmetics, and pharmaceuticals.^[3]

General Description

Pink crystals or white waxy solid.

EXPOSURE ROUTES

inhalation, skin absorption, ingestion, skin and/or eye contact

FIRST AID

(See procedures) Eye:Irrigate immediately Skin:Soap flush immediately Breathing:Respiratory support Swallow:Medical attention immediately

Consumer Uses

This substance is used in the following products: cosmetics and personal care products. Other release to the environment of this substance is likely to occur from: indoor use as processing aid.