1,4-Benzoquinone
[CAS# 106-51-4]

Identification

• Classification: Organic raw materials >> Quinones
• Name: 1,4-Benzoquinone
• Synonyms: 2,5-Cyclohexadiene-1,4-dione; Quinone; Quinone; p-Benzoquinone 98+ % (dried); 2,5-Cyclohexadiene-1,4-dione
• Molecular Formula: C₆H₄O₂
• Molecular Weight: 108.10
• CAS Registry Number: 106-51-4
• EC Number: 203-405-2
• SMILES: C1=CC(=O)C=CC1=O

Properties

• Density: 1.318 g/mL
• Melting point: 112-116 °C
• Boiling point: 293 °C
• Flash point: 38 °C
• Water solubility: 10 g/L (25 °C)

Safety Data

• Hazard Symbols: GHS06;GHS07;GHS08;GHS09 Danger
• Risk Statements: H301+H331-H301-H315-H317-H319-H331-H335-H341=H400-H410
• Safety Statements: P203-P261-P264-P264+P265-P270-P271-P272-P273-P280-P301+P316-P302+P352-P304+P340-P305+P351+P338-P316-P318-P319-P321-P330-P332+P317-P333+P317-P337+P317-P362+P364-P391-P403+P233-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Acute hazardous to the aquatic environment	Aquatic Acute	1	H400
Acute toxicity	Acute Tox.	3	H301
Skin irritation	Skin Irrit.	2	H315
Eye irritation	Eye Irrit.	2	H319
Specific target organ toxicity - single exposure	STOT SE	3	H335
Acute toxicity	Acute Tox.	3	H331
Chronic hazardous to the aquatic environment	Aquatic Chronic	1	H410
Skin sensitization	Skin Sens.	1	H317
Germ cell mutagenicity	Muta.	2	H341
Flammable solids	Flam. Sol.	1	H228
Acute toxicity	Acute Tox.	3	H311
Skin corrosion	Skin Corr.	1	H314
Serious eye damage	Eye Dam.	1	H318
Eye irritation	Eye Irrit.	2A	H319
Skin corrosion	Skin Corr.	1B	H314

• Transport Information: UN 2587

Discovery and Applications

1,4-Benzoquinone, commonly referred to as quinone, is a chemical compound known for its distinctive yellow crystalline appearance and its wide range of applications across various industries. Its discovery dates back to the early 19th century when scientists began exploring the oxidation of aromatic compounds. As one of the simplest quinones, 1,4-benzoquinone has since gained significant attention due to its role in redox chemistry and its application in fields such as organic synthesis, electrochemistry, and biological research.

The molecular structure of 1,4-benzoquinone consists of a six-membered carbon ring with alternating double bonds and two carbonyl groups positioned at the 1 and 4 positions of the ring. This arrangement gives the molecule its distinctive oxidative properties, making it highly reactive in both reduction and oxidation processes. The discovery of 1,4-benzoquinone occurred during studies on the oxidation of hydroquinone, its reduced form, and led to insights into its redox behavior, which has been crucial to its various applications.

One of the earliest uses of 1,4-benzoquinone was in the dye industry, where it was utilized as an oxidizing agent in the synthesis of various organic pigments. Its ability to accept electrons and participate in redox reactions made it an essential component in the production of dyes and pigments that require stable, intense colors. Over time, the use of quinone expanded into other industries, including the rubber industry, where it was employed as a vulcanizing agent to improve the elasticity and durability of rubber products.

In organic chemistry, 1,4-benzoquinone is widely used as an intermediate in various synthetic processes. It is often employed as an oxidizing agent in reactions that require the conversion of alcohols to ketones or in dehydrogenation processes. Its ability to act as a mild oxidant makes it valuable in selective oxidation reactions, where harsh oxidants could potentially damage sensitive functional groups. This has made 1,4-benzoquinone a popular reagent in laboratory-scale organic synthesis and industrial chemical production.

1,4-Benzoquinone also has significant applications in electrochemistry, particularly in the development of batteries and electrochemical cells. Its redox properties make it a suitable candidate for electron-transfer reactions, which are crucial in energy storage devices. Quinones have been explored as potential materials for organic batteries, where their ability to undergo reversible redox reactions could provide a sustainable and environmentally friendly alternative to traditional battery materials. In this context, 1,4-benzoquinone and its derivatives are being studied for their potential to improve the efficiency and capacity of rechargeable batteries.

In biological research, 1,4-benzoquinone has been of interest due to its role in electron transport chains and its reactivity with biological molecules. Quinones are naturally occurring compounds in many biological systems, where they play a vital role in processes such as cellular respiration and photosynthesis. The study of 1,4-benzoquinone has provided insights into the mechanisms of redox reactions in living organisms and the behavior of quinones as electron carriers. Additionally, its ability to interact with proteins and enzymes has led to research on its potential therapeutic applications, including its role in cancer treatment and as a model compound for studying oxidative stress in cells.

Despite its wide range of applications, 1,4-benzoquinone is also known for its potential toxicity. Prolonged exposure to the compound can lead to irritation of the skin, eyes, and respiratory system. As a result, safety measures are necessary when handling the substance, particularly in industrial and laboratory settings. However, ongoing research aims to develop safer and more sustainable methods for using 1,4-benzoquinone in various applications.

The discovery of 1,4-benzoquinone has had a lasting impact on several scientific fields. From its use in dyes and rubber processing to its role in organic synthesis, electrochemistry, and biological research, the compound continues to be an important tool in modern chemistry. As research progresses, new applications and safer handling methods for 1,4-benzoquinone will likely emerge, ensuring its continued relevance in both industrial and scientific contexts.

References

1994. Erythroid progenitor cells that survive benzene exposure exhibit greater resistance to the toxic benzene metabolites benzoquinone and hydroquinone. Archives of Toxicology, 68(8), 535-540.
DOI: 10.1007/s002040050110

1994. Oxidative coupling of mithramycin and hydroquinone catalyzed by copper oxidases and benzoquinone. Implications for the mechanism of action of aureolic acid antibiotics. Bioorganic & Medicinal Chemistry, 2(6), 473-482.
DOI: 10.1016/0968-0896(94)80025-1

1984. In vitro effects of benzene metabolites on mouse bone marrow stromal cells. Toxicology and Applied Pharmacology, 76(1), 45-55.
DOI: 10.1016/0041-008x(84)90027-9