2,4-Dinitrophenol

Chemical structure of 2,4-Dinitrophenol

2,4-Dinitrophenol (DNP) is an organic compound with the formula C₆H₄N₂O₅. It is a yellow, crystalline solid that has been used in various industrial applications and as a weight loss aid. DNP is known for its ability to uncouple oxidative phosphorylation, leading to increased metabolic rate and energy expenditure.

Chemical Properties

2,4-Dinitrophenol is a nitrophenol, characterized by the presence of two nitro groups (NO₂) at the 2 and 4 positions on the phenol ring. This compound is a weak acid and can form salts with bases. It is soluble in organic solvents and slightly soluble in water.

Mechanism of Action

DNP acts as a protonophore, allowing protons to leak across the mitochondrial membrane. This uncouples oxidative phosphorylation, disrupting the proton gradient and leading to increased heat production and energy expenditure. As a result, the body burns more calories, which can lead to weight loss.

Historical Use

In the 1930s, 2,4-Dinitrophenol was marketed as a weight loss drug. However, due to its severe side effects, including hyperthermia, tachycardia, and even death, it was banned for human consumption. Despite this, it has been used illicitly for weight loss purposes.

Industrial Applications

DNP is used in the manufacture of dyes, wood preservatives, and as a photographic developer. It is also employed as an intermediate in the synthesis of other chemicals.

Safety and Toxicity

Exposure to 2,4-Dinitrophenol can be hazardous. It is toxic if ingested, inhaled, or absorbed through the skin. Symptoms of DNP poisoning include fever, sweating, nausea, and vomiting. Chronic exposure can lead to cataracts and skin lesions.

Synthesis

Synthesis of 2,4-Dinitrophenol

2,4-Dinitrophenol can be synthesized by the nitration of phenol using a mixture of nitric acid and sulfuric acid. The reaction involves the substitution of hydrogen atoms on the phenol ring with nitro groups.

Related Pages

• Phenol
• Oxidative phosphorylation
• Mitochondrial membrane
• Protonophore

Gallery

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  2,4-Dinitrophenol crystals
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  Histogram of DNP doses
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  Nitro reduction of DNP
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  DNP chamber of horrors