Cyanuric chloride

Structural formula
General
Surname	Cyanuric chloride
other names	2,4,6-trichloro-1,3,5-triazine; Trichloro- S- triazine; TCT; Cyanuric acid chloride; Cyanuric acid trichloride; Tricyanogen chloride; Trichlorocyanidine; Cyanuryl chloride;
Molecular formula	C 3 Cl 3 N 3
Brief description	white solid with a chlorine-like odor
External identifiers / databases
EC number	203-614-9
ECHA InfoCard	100.003.287
PubChem	7954
Wikidata	Q419742
properties
Molar mass	184.41 g mol −1
Physical state	firmly
density	1.92 g cm −3 (20 ° C)
Melting point	146 ° C
boiling point	194 ° C
Vapor pressure	1 Pa (20 ° C)
solubility	violent decomposition in water
safety instructions
H and P phrases	H: 302-330-314-317-335
	EUH: 014
	P: 260-280-284-305 + 351 + 338-310-402 + 404
Toxicological data	485 mg kg −1 ( LD 50 , rat , oral )
	As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Cyanuric chloride is a reactive heterocyclic compound and a halogenated heteroaromatic . The eponymous basic building block is the cyanuric acid (1,3,5-triazine-2,4,6-triol) derived from 1,3,5-triazine (see also Hantzsch-Widman system ).

Extraction and presentation

Cyanuric chloride is in two stages by the trimerization of cyanogen chloride produced. In the first step, hydrocyanic acid is halogenated with chlorine to form cyanogen chloride, which is then trimerized at an elevated temperature on a carbon contact:

{\ displaystyle \ mathrm {HCN + Cl_ {2} \ longrightarrow ClCN + HCl}}

{\ displaystyle \ mathrm {3 \, ClCN \ longrightarrow (ClCN) _ {3}}}

In 2005 around 200,000 tons were produced worldwide.

properties

Cyanuric chloride is a white, finely crystalline powder. It irritates the mucous membranes and has a peculiar, pungent odor similar to chlorine or acid chloride. In dry air, even at elevated temperatures, it is stable; in the presence of traces of moisture, it hydrolyzes to cyanuric acid and HCl. The rate of hydrolysis is heavily dependent on temperature and pH. It is stable for several hours in ice-water as a suspension, buffered to pH = 7; above 10 ° C., the hydrolysis increases rapidly with increasing temperature, in which the hydrochloric acid formed during the hydrolysis has an autocatalytic effect. Alcohols also react analogously with cyanuric chloride in a strongly exothermic reaction. The three chlorine substituents in cyanuric chloride differ considerably in their reactivity towards nucleophiles . With a suitable choice of the reaction conditions it is possible to selectively react these with three different nucleophiles Nu ¹ to Nu ³ :

It reacts violently with solvents such as N, N-dimethylformamide and dimethyl sulfoxide in a strongly exothermic reaction.

use

Cyanuric chloride is an important intermediate in the production of direct dyes , reactive dyes for cotton , optical brighteners and pesticides . Many reactive dyes are derived from dichlorotriazines and in particular from monochlorotriazines.

Risk assessment

In 2016, cyanuric chloride was included in the EU's ongoing action plan ( CoRAP ) in accordance with Regulation (EC) No. 1907/2006 (REACH) as part of substance evaluation . The effects of the substance on human health and the environment are re-evaluated and, if necessary, follow-up measures are initiated. The reasons for the uptake of cyanuric chloride were concerns about environmental exposure and high (aggregated) tonnage as well as the dangers arising from a possible assignment to the group of PBT / vPvB substances and the possible risk from reproductive properties. The re-evaluation took place from 2017 and was carried out by Poland . A final report was then published.

Individual evidence

↑ ^a ^b ^c ^d ^e ^f ^g ^h Entry on 2,4,6-trichloro-1,3,5-triazine in the GESTIS substance database of the IFA , accessed on January 8, 2018(JavaScript required) .
↑ Data sheet cyanuric chloride (PDF) from Merck , accessed on June 15, 2017.
↑ Entry on 2,4,6-trichloro-1,3,5-triazine in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA), accessed on February 1, 2016. Manufacturers or distributors can expand the harmonized classification and labeling .
^ Klaus Huthmacher, Dieter Most: Cyanuric Acid and Cyanuric Chloride . In: Ullmann's Encyclopedia of Industrial Chemistry, 2005, Wiley-VCH, Weinheim. doi : 10.1002 / 14356007.a08_191 .
↑ ^a ^b ^c L. Roth, U. Weller-Schäferbarthold: Hazardous chemical reactions - Potentially dangerous chemical reactions to over 1750 substances , entry for cyanuric chloride, CD-ROM edition 4/2019, ecomed Sicherheit Landsberg / Lech, ISBN 978-3- 609-48040-4 .
↑ European Chemicals Agency (ECHA): Substance Evaluation Conclusion and Evaluation Report .
↑ Community rolling action plan ( CoRAP ) of the European Chemicals Agency (ECHA): 2,4,6-trichloro-1,3,5-triazine , accessed on March 26, 2019.

[GESTIS-1] ↑ ^a ^b ^c ^d ^e ^f ^g ^h Entry on 2,4,6-trichloro-1,3,5-triazine in the GESTIS substance database of the IFA , accessed on January 8, 2018(JavaScript required) .

[Merck-2] Data sheet cyanuric chloride (PDF) from Merck , accessed on June 15, 2017.

[CLP_100.003.287-3] Entry on 2,4,6-trichloro-1,3,5-triazine in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA), accessed on February 1, 2016. Manufacturers or distributors can expand the harmonized classification and labeling .

[Ullmann-4] Klaus Huthmacher, Dieter Most: Cyanuric Acid and Cyanuric Chloride . In: Ullmann's Encyclopedia of Industrial Chemistry, 2005, Wiley-VCH, Weinheim. doi : 10.1002 / 14356007.a08_191 .

[Roth_Weller_CD-ROM-5] L. Roth, U. Weller-Schäferbarthold: Hazardous chemical reactions - Potentially dangerous chemical reactions to over 1750 substances , entry for cyanuric chloride, CD-ROM edition 4/2019, ecomed Sicherheit Landsberg / Lech, ISBN 978-3- 609-48040-4 .

[6] European Chemicals Agency (ECHA): Substance Evaluation Conclusion and Evaluation Report .

[7] Community rolling action plan ( CoRAP ) of the European Chemicals Agency (ECHA): 2,4,6-trichloro-1,3,5-triazine , accessed on March 26, 2019.