Xylidine can refer to any of the six

isomer In chemistry, isomers are molecules or polyatomic ions with identical molecular formula – that is, the same number of atoms of each element (chemistry), element – but distinct arrangements of atoms in space. ''Isomerism'' refers to the exi ...

s of

xylene In organic chemistry, xylene or xylol (; IUPAC name: dimethylbenzene) are any of three organic compounds with the formula . They are derived from the substitution of two hydrogen atoms with methyl groups in a benzene ring; which hydrogens are su ...

amine In chemistry, amines (, ) are organic compounds that contain carbon-nitrogen bonds. Amines are formed when one or more hydrogen atoms in ammonia are replaced by alkyl or aryl groups. The nitrogen atom in an amine possesses a lone pair of elec ...

, or any mixture of them. The chemical formula of xylidines is C₈H₁₁N or, more descriptively, (CH₃)₂C₆H₃NH₂. The CAS number for the isomer mixture is 1300-73-8. They are colorless solids or liquids, although commercial samples can appear yellow or darker. They are miscible with

ethanol Ethanol (also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound with the chemical formula . It is an Alcohol (chemistry), alcohol, with its formula also written as , or EtOH, where Et is the ps ...

and

diethyl ether Diethyl ether, or simply ether, is an organic compound with the chemical formula , sometimes abbreviated as . It is a colourless, highly Volatility (chemistry), volatile, sweet-smelling ("ethereal odour"), extremely flammable liquid. It belongs ...

and slightly soluble in water. Xylidines are used in production of

pigment A pigment is a powder used to add or alter color or change visual appearance. Pigments are completely or nearly solubility, insoluble and reactivity (chemistry), chemically unreactive in water or another medium; in contrast, dyes are colored sub ...

s and

dye Juan de Guillebon, better known by his stage name DyE, is a French musician. He is known for the music video of the single "Fantasy Fantasy is a genre of speculative fiction that involves supernatural or Magic (supernatural), magical ele ...

stuffs, and various

antioxidant Antioxidants are Chemical compound, compounds that inhibit Redox, oxidation, a chemical reaction that can produce Radical (chemistry), free radicals. Autoxidation leads to degradation of organic compounds, including living matter. Antioxidants ...

agrochemical An agrochemical or agrichemical, a contraction of ''agricultural chemical'', is a chemical product used in industrial agriculture. Agrichemical typically refers to biocides (pesticides including insecticides, herbicides, fungicides and nematicide ...

s, pharmaceuticals,

hypergolic propellant A hypergolic propellant is a rocket propellant combination used in a rocket engine, whose components spontaneously ignite when they come into contact with each other. The two propellant components usually consist of a fuel and an oxidizer. The ...

s, and many other organic chemicals. In

World War II World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

, xylidine was an important

antiknock agent An antiknock agent (also: knock inhibitor) is a gasoline additive used to reduce engine knocking and increase the fuel's octane rating by raising the temperature and pressure at which auto-ignition occurs. The mixture known as gasoline or petrol, ...

in very high performance aviation gasolines. Its purpose was to permit high levels of boost pressure in multiple-stage turbochargers, and thus high power at high altitudes, without causing detonation that would destroy the engine. The high pressures brought high temperatures of inlet air, making engines prone to knock. This use and storage stabilization methods were important military secrets.

Isomers of xylidine

Image:2,3-Xylidin.svg, 2,3-xylidine Image:2,4-Xylidin.svg, 2,4-xylidine Image:2,5-Xylidin.svg, 2,5-xylidine Image:2,6-Xylidin.svg, 2,6-xylidine Image:3,4-Xylidin.svg, 3,4-xylidine Image:3,5-Xylidin.svg, 3,5-xylidine

2,3-Xylidine

2,3-Xylidine, also called ''o-xylidine'', ''2,3-dimethylaniline'', ''2,3-xylylamine'', or ''2,3-dimethylphenylamine'', is a liquid with melting point 2.5 °C and boiling point 222 °C, and

flash point The flash point of a material is the "lowest liquid temperature at which, under certain standardized conditions, a liquid gives off vapours in a quantity such as to be capable of forming an ignitable vapour/air mixture". The flash point is somet ...

at 96 °C. It is used in production of

mefenamic acid Mefenamic acid is a member of the Nonsteroidal anti-inflammatory drug#Anthranilic acid derivatives .28fenamates.29, anthranilic acid derivatives (or fenamate) class of nonsteroidal anti-inflammatory drugs (NSAIDs), and is used to treat mild to m ...

, dyes, and pesticides.

2,4-Xylidine

2,4-Xylidine, also called ''2-methyl-p-toluidine'', ''2,4-dimethylaniline'', ''2,4-xylylamine'', or ''2,4-dimethylphenylamine'', is a liquid with melting point 16 °C, boiling point 217 °C, and

at 90 °C. It is used for production of pesticides, dyes, and other chemicals.

2,5-Xylidine

2,5-Xylidine, also called ''p-xylidine'', ''2,5-dimethylaniline'', ''2,5-xylylamine'', or ''2,5-dimethylphenylamine'', is a liquid with melting point 11.5 °C and boiling point 215 °C. It is used for production of dyes and other chemicals.

2,6-Xylidine

2,6-Xylidine, also called ''2,6-dimethylaniline'', ''2,6-xylylamine'', or ''2,6-dimethylphenylamine'', is a liquid with melting point 8.4 °C and boiling point 216 °C. It is used in production of some anesthetics and other chemicals.

3,4-Xylidine

3,4-Xylidine, also called ''3,4-dimethylaniline'', ''3,4-xylylamine'', or ''3,4-dimethylphenylamine'', is a crystalline solid with melting point 51 °C and boiling point 226 °C. It is used as a raw material for production of vitamin B₂, dyes, pesticides, and other chemicals.

3,5-Xylidine

3,5-Xylidine, also called ''3,5-dimethylaniline'', ''3,5-xylylamine'', or ''3,5-dimethylphenylamine'', is a liquid with melting point 9.8 °C and boiling point 220–221 °C. It is used for production of pesticides, dyes, and other chemicals.

Safety

The U.S.

Occupational Safety and Health Administration The Occupational Safety and Health Administration (OSHA; ) is a regulatory agency of the United States Department of Labor that originally had federal visitorial powers to inspect and examine workplaces. The United States Congress established ...

(OSHA) has set the legal limit (

Permissible exposure limit The permissible exposure limit (PEL or OSHA PEL) is a legal limit in the United States for exposure of an employee to a chemical substance or physical agents such as high level noise. Permissible exposure limits were established by the Occupational ...

) for xylidine exposure in the workplace as 5 ppm (25 mg/m³) skin exposure over an eight-hour workday. The U.S.

National Institute for Occupational Safety and Health The National Institute for Occupational Safety and Health (NIOSH, ) is the List of United States federal agencies, United States federal agency responsible for conducting research and making recommendations for the prevention of work-related occ ...

(NIOSH) has set a

Recommended exposure limit A recommended exposure limit (REL) is an occupational exposure limit that has been recommended by the United States National Institute for Occupational Safety and Health. The REL is a level that NIOSH believes would be protective of worker safety ...

(REL) of 2 ppm (10 mg/m³) skin exposure over an eight-hour workday. At levels of 50 ppm, xylidine is

immediately dangerous to life and health The term immediately dangerous to life or health (IDLH) is defined by the US National Institute for Occupational Safety and Health (NIOSH) as exposure to airborne contaminants that is "likely to cause death or immediate or delayed permanent adver ...

. Their hazard and precaution phrases are .

References

{{Authority control Anilines Alkyl-substituted benzenes