2,4-Dinitrochlorobenzene (DNCB) is an

organic compound Some chemical authorities define an organic compound as a chemical compound that contains a carbon–hydrogen or carbon–carbon bond; others consider an organic compound to be any chemical compound that contains carbon. For example, carbon-co ...

with the

chemical formula A chemical formula is a way of presenting information about the chemical proportions of atoms that constitute a particular chemical compound or molecule, using chemical element symbols, numbers, and sometimes also other symbols, such as pare ...

(O₂N)₂C₆H₃Cl. It is a yellow solid that is

soluble In chemistry, solubility is the ability of a substance, the solute, to form a solution with another substance, the solvent. Insolubility is the opposite property, the inability of the solute to form such a solution. The extent of the solubi ...

organic solvents A solvent (from the Latin language, Latin ''wikt:solvo#Latin, solvō'', "loosen, untie, solve") is a substance that dissolves a solute, resulting in a Solution (chemistry), solution. A solvent is usually a liquid but can also be a solid, a gas ...

. It is an intermediate for the industrial production of other compounds.

Preparation and reactions

DNCB is produced commercially by the

nitration In organic chemistry, nitration is a general class of chemical processes for the introduction of a nitro group () into an organic compound. The term also is applied incorrectly to the different process of forming nitrate esters () between Alcohol ...

of ''p''-nitrochlorobenzene with a mixture of nitric and

sulfuric acid Sulfuric acid (American spelling and the preferred IUPAC name) or sulphuric acid (English in the Commonwealth of Nations, Commonwealth spelling), known in antiquity as oil of vitriol, is a mineral acid composed of the elements sulfur, oxygen, ...

s. Other methods afford the compound less efficiently include the chlorination of

1,3-dinitrobenzene 1,3-Dinitrobenzene is one of three isomers of dinitrobenzene, with the formula C6H4(NO2)2. It is one of three isomers of dinitrobenzene. The compound is a yellow solid that is soluble in organic solvents. Preparation 1,3-Dinitrobenzene is acc ...

, nitration of o-nitrochlorobenzene and the dinitration of

chlorobenzene Chlorobenzene (abbreviated PhCl) is an aryl chloride and the simplest of the chlorobenzenes, consisting of a benzene ring substituted with one chlorine atom. Its chemical formula is C6H5Cl. This colorless, flammable liquid is a common solvent a ...

. By virtue of the two nitro substituents, the chloride in DNCB is particularly susceptible to

nucleophilic substitution In chemistry, a nucleophilic substitution (SN) is a class of chemical reactions in which an electron-rich chemical species (known as a nucleophile) replaces a functional group within another electron-deficient molecule (known as the electrophile) ...

, at least relative to simple

. In this way, the compound is a precursor to many other compounds. In one example, DNCB is as a substrate in Glutathione S-Transferase, relevant to activity assays.

Safety

DNCB induces a

type IV hypersensitivity Type IV hypersensitivity, in the Gell and Coombs classification of allergic reactions, often called delayed-type hypersensitivity, is a type of hypersensitivity reaction that can take a day or more to develop. Unlike the other types, it is not ...

reaction in almost all people exposed to it, so it is used medically to assess the

T cell T cells (also known as T lymphocytes) are an important part of the immune system and play a central role in the adaptive immune response. T cells can be distinguished from other lymphocytes by the presence of a T-cell receptor (TCR) on their cell ...

activity in patients. This is a useful diagnostic test for immunocompromised patients. It can also be used to treat

warts Warts are non-cancerous viral growths usually occurring on the hands and feet but which can also affect other locations, such as the genitals or face. One or many warts may appear. They are distinguished from cancerous tumors as they are caus ...

. DNCB can cause

contact dermatitis Contact dermatitis is a type of acute or chronic inflammation of the skin caused by exposure to chemical or physical agents. Symptoms of contact dermatitis can include itchy or dry skin, a red rash, bumps, blisters, or swelling. These rashes ...

References

{{DEFAULTSORT:Dinitrochlorobenzene, 2, 4- Nitrobenzene derivatives Chlorobenzene derivatives