4-Methylbenzophenone
[CAS# 134-84-9]

Identification

• Classification: Chemical reagent >> Organic reagent >> Aromatic ketone
• Name: 4-Methylbenzophenone
• Synonyms: (4-Methylphenyl)phenylmethanone; Phenyl p-tolyl ketone
• Molecular Formula: C₁₄H₁₂O
• Molecular Weight: 196.25
• CAS Registry Number: 134-84-9
• EC Number: 205-159-1
• SMILES: CC1=CC=C(C=C1)C(=O)C2=CC=CC=C2

Properties

• Melting point: 53-57 °C
• Boiling point: 326 °C
• Flash point: 143 °C

Safety Data

• Hazard Symbols: GHS07;GHS08 Warning
• Risk Statements: H302-H319-H373-H412
• Safety Statements: P260-P264-P264+P265-P270-P273-P280-P301+P317-P305+P351+P338-P319-P330-P337+P317-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Eye irritation	Eye Irrit.	2	H319
Acute toxicity	Acute Tox.	4	H302
Specific target organ toxicity - repeated exposure	STOT RE	2	H373
Chronic hazardous to the aquatic environment	Aquatic Chronic	3	H412
Chronic hazardous to the aquatic environment	Aquatic Chronic	2	H411
Acute toxicity	Acute Tox.	3	H301
Skin irritation	Skin Irrit.	2	H315
Specific target organ toxicity - single exposure	STOT SE	3	H335

Discovery and Applications

4-Methylbenzophenone, also known as 4-methyl-2,2-diphenyl-1-pentanone, is a chemical compound with notable applications in the field of organic chemistry and materials science. This compound is characterized by its structure, which includes a benzophenone backbone with a methyl group attached at the para position of one of the phenyl rings.

The discovery of 4-methylbenzophenone can be traced to studies on benzophenone derivatives, which began in the early 20th century. Researchers were interested in modifying the benzophenone structure to enhance its properties for various applications. The addition of a methyl group to the benzophenone framework was found to influence the compound's chemical behavior and functional properties.

One of the primary applications of 4-methylbenzophenone is as a UV filter. In this role, it serves to absorb ultraviolet (UV) light and protect other materials from UV-induced degradation. This property is particularly useful in the formulation of sunscreens, where 4-methylbenzophenone helps shield the skin from harmful UV radiation. By absorbing UV light, the compound reduces the risk of sunburn and long-term skin damage.

In addition to its use in sunscreens, 4-methylbenzophenone is employed in the plastics and coatings industries as a UV stabilizer. Its ability to absorb UV radiation makes it valuable for protecting polymers and other materials from UV degradation. When incorporated into plastic formulations, 4-methylbenzophenone helps extend the lifespan of products exposed to sunlight by preventing color fading and material breakdown.

The compound is also utilized in the synthesis of various organic chemicals and as an intermediate in the production of pharmaceuticals. Its reactivity and ability to undergo various chemical transformations make it a useful building block in organic synthesis.

Despite its useful applications, there are considerations regarding the environmental and health impacts of 4-methylbenzophenone. As with many UV filters, there is ongoing research into its potential effects on human health and the environment. The compound’s ability to absorb UV light can sometimes lead to the formation of potentially harmful byproducts. Consequently, there is a growing interest in developing safer alternatives and improving the safety profiles of UV filters used in consumer products.

Overall, 4-methylbenzophenone is an important chemical compound with significant applications in UV protection for both personal care products and industrial materials. Its role in enhancing the durability and effectiveness of various products underscores its value in modern chemistry and material science.

References

2019. An Example of Ketone Olefination via Praseodymium-Mediated Barbier Reaction in the Presence of Diethyl Phosphite. Synlett, 30(11).
DOI: 10.1055/s-0039-1690096

2022. Palladium-Catalyzed Synthesis of Aryl Ketones from Carboxylic Acids and Arylboronic Acids Using 2-Chloroimidazolium Chloride as a Coupling Reagent. Synthesis, 54(17).
DOI: 10.1055/a-1848-3399

2023. Chemical characterization of virgin and recycled polyethylene terephthalate films used for food contact applications. European Food Research and Technology, 249(8).
DOI: 10.1007/s00217-023-04400-z