Cyanuric chloride 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

formula In science, a formula is a concise way of expressing information symbolically, as in a mathematical formula or a ''chemical formula''. The informal use of the term ''formula'' in science refers to the general construct of a relationship betwe ...

(NCCl)₃. This white solid is the

chlorinated In chemistry, halogenation is a chemical reaction which introduces one or more halogens into a chemical compound. Halide-containing compounds are pervasive, making this type of transformation important, e.g. in the production of polymers, drugs. ...

derivative of 1,3,5-triazine. It is the trimer of

cyanogen chloride Cyanogen chloride is an inorganic compound with the formula . This triatomic pseudohalogen is an easily condensed colorless gas. More commonly encountered in the laboratory is the related compound cyanogen bromide, a room-temperature solid that is ...

. Cyanuric chloride is the main precursor to the popular but controversial herbicide

atrazine Atrazine ( ) is a Organochlorine compound, chlorinated herbicide of the triazine class. It is used to prevent pre-emergence broadleaf weeds in crops such as maize (corn), soybean and sugarcane and on turf, such as golf courses and residential law ...

Production

Cyanuric chloride is prepared in two steps from

hydrogen cyanide Hydrogen cyanide (formerly known as prussic acid) is a chemical compound with the chemical formula, formula HCN and structural formula . It is a highly toxic and flammable liquid that boiling, boils slightly above room temperature, at . HCN is ...

via the intermediacy of

, which is trimerized at elevated temperatures over a carbon catalyst: :HCN + Cl₂ → ClCN + HCl : Cyanurchloride Synthesis V

In 2005, approximately 200,000 tons were produced.Klaus Huthmacher, Dieter Most "Cyanuric Acid and Cyanuric Chloride" in Ullmann's Encyclopedia of Industrial Chemistry, 2005, Wiley-VCH, Weinheim. .

Industrial uses

It is estimated that 70% of cyanuric chloride is used in the preparation of the triazine-class pesticides, especially

. Such reactions rely on the easy displacement of the chloride with

nucleophile In chemistry, a nucleophile is a chemical species that forms bonds by donating an electron pair. All molecules and ions with a free pair of electrons or at least one pi bond can act as nucleophiles. Because nucleophiles donate electrons, they are ...

s such as amines: :(ClCN)₃ + 2 RNH₂ → (RNHCN)(ClCN)₂ + RNH₃⁺Cl⁻ Other triazine herbicides, such as simazine, anilazine and cyromazine are made in an analogous way.Ashford's Dictionary of Industrial Chemicals, 3rd edition, 2011, pages 2495-8 Cyanuric chloride is also used as a precursor to dyes and crosslinking agents. The largest class of these dyes are the sulfonated triazine-stilbene optical brighteners (OBA) or fluorescent whitening agents (FWA) commonly found in detergent formulas and white paper. Many reactive dyes also incorporate a triazine ring. They are also manufactured by way of the chloride displacement reaction shown above.

Reactivity

The chloride centers are easily replaced.

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 ...

s give

melamine Melamine is an organic compound with the formula C3H6N6. This white solid is a trimer (chemistry), trimer of cyanamide, with a 1,3,5-Triazine, 1,3,5-triazine skeleton. Like cyanamide, it contains 66% nitrogen by mass, and its derivatives ha ...

derivatives, for example in the synthesis of

dendrimer Dendrimers are highly ordered, Branching (polymer chemistry), branched molecules, polymeric molecules. Synonymous terms for dendrimer include arborols and cascade molecules. Typically, dendrimers are symmetric about the core, and often adopt a sph ...

s: : It reacts with hydrosulfide to give thiocyanuric acid ().

Organic synthesis

Cyanuric chloride is employed as a

reagent In chemistry, a reagent ( ) or analytical reagent is a substance or compound added to a system to cause a chemical reaction, or test if one occurs. The terms ''reactant'' and ''reagent'' are often used interchangeably, but reactant specifies a ...

organic synthesis Organic synthesis is a branch of chemical synthesis concerned with the construction of organic compounds. Organic compounds are molecules consisting of combinations of covalently-linked hydrogen, carbon, oxygen, and nitrogen atoms. Within the gen ...

for the conversion of alcohols into alkyl chlorides, and carboxylic acids into acyl chlorides: : It is also used as a dehydrating agent, e.g. in the conversion of amides to

nitriles In organic chemistry, a nitrile is any organic compound that has a functional group. The name of the compound is composed of a base, which includes the carbon of the , suffixed with "nitrile", so for example is called "propionitrile" (or pro ...

, and for the activation of carboxylic acids for reduction to alcohols. Heating with DMF gives "Gold's reagent" Me₂NCH=NCH=NMe₂⁺Cl⁻, which is a versatile source of aminoalkylations and a precursor to heterocycles. Cyanuric chloride can also be used as an alternative to oxalyl chloride in the Swern oxidation.

References

{{Reflist Inorganic chlorine compounds Triazines Trimers (chemistry) Dehydrating agents

Production

Industrial uses

Reactivity

Organic synthesis

See also

References