Adiponitrile

Structural formula
General
Surname	Adiponitrile
other names	ADN Adiponitrile Adipic acid dinitrile Hexanedioic dinitrile 1,4-dicyanobutane
Molecular formula	C 6 H 8 N 2
Brief description	colorless, almost odorless liquid
External identifiers / databases
CAS number 111-69-3 EC number 203-896-3 ECHA InfoCard 100.003.543 PubChem 8128 Wikidata Q84062
properties
Molar mass	108.14 g mol −1
Physical state	liquid
density	0.96 g cm −3
Melting point	2.3 ° C
boiling point	295 ° C
Vapor pressure	0.3 Pa (20 ° C)
solubility	soluble in water (50 g l −1 at 20 ° C)
Refractive index	1.4380 (20 ° C)
safety instructions
GHS labeling of hazardous substances danger H and P phrases H: 301-332 P: 261-301 + 330 + 331-310
Toxicological data	155 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 . Refractive index: Na-D line , 20 ° C

Adiponitrile (ADN, Adipinsäuredinitril, Hexandisäuredinitril) belongs to the aliphatic nitriles and is an intermediate product of the polyamide production .

Manufacturing

Adiponitrile is mainly produced by the hydrocyanation of 1,3-butadiene . In this case, hydrogen cyanide using a nickel catalyst to the double bonds is added the butadiene.

Two other processes are based on the dimerization of acrylonitrile .

• The electrochemical reduction leads directly to adiponitrile via hydrodimerization. The cell for electrosynthesis contains anodically diluted sulfuric acid and cathodically separated via a diaphragm an aqueous solution of acrylonitrile and salts of 4-toluenesulfonic acid as a solubilizer for the slightly water-soluble acrylonitrile.

${\displaystyle \mathrm {2\ CH_{2}{=}CH{-}CN+2\ H^{+}+2\ e^{-}\longrightarrow NC{-}(CH_{2})_{4}{-}CN} }$

• The catalytic dimerization gives unsaturated hexenedinitrile, which is hydrogenated to adiponitrile .

In the laboratory, it can be produced by nucleophilic substitution of 1,4-dichlorobutane with NaCN in DMSO .

A biotechnological process for the production of adiponitrile was recently reported, in which the use of toxic hydrogen cyanide (or cyanides) is dispensed with. The key step is the double elimination of water from the hexanedialdoxime, during which adiponitrile is formed. This step is catalyzed by an aldoxime dehydratase.

use

Adiponitrile is extensively hydrogenated to hexamethylenediamine . Adipic acid can be produced by hydrolysis of the nitrile groups. Both products are required for the manufacture of PA6.6 .

Individual evidence

1. ↑ ^{a b c d e f g h i} Entry on adiponitrile in the GESTIS substance database of the IFA , accessed on January 10, 2017(JavaScript required) .
2. ↑ David R. Lide (Ed.): CRC Handbook of Chemistry and Physics . 90th edition. (Internet version: 2010), CRC Press / Taylor and Francis, Boca Raton, FL, Physical Constants of Organic Compounds, pp. 3-10.
3. ↑ Wolfgang-Dieter Luz, Eberhard Zirngiebl: The future of electrochemistry. In: Chemistry in Our Time. 23, 1989, pp. 151-160, doi : 10.1002 / ciuz.19890230503
4. ↑ Synthesis of adiponitrile - PrepChem.com. Accessed July 11, 2018 . 
5. ↑ Harald Gröger : Biocatalysis - Solution approaches along the chemical value chain BIOspektrum 25 (2019), pp. 786–789, doi: 10.1007 / s12268-019-0093-3 .
6. ↑ T. Betke, M. Maier, H. Gruber-Wölfler, H. Gröger: Biocatalytic production of adiponitrile and related aliphatic linear α, ω-dinitriles , Nature Commun. 2018, 9, 5112, doi: 10.1038 / s41467-018-0743-0 .