Hexamethylenediamine

Structural formula
General
Surname	Hexamethylenediamine
other names	1,6-diaminohexane Hexane-1,6-diamine 1,6-HEXANEDIAMINE ( INCI )
Molecular formula	C 6 H 16 N 2
Brief description	hygroscopic, silky glossy leaves with an ammonia-like odor
External identifiers / databases
CAS number 124-09-4 EC number 204-679-6 ECHA InfoCard 100.004.255 PubChem 16402 ChemSpider 13835579 DrugBank DB03260 Wikidata Q424936
properties
Molar mass	116.21 g mol −1
Physical state	firmly
density	0.89 g cm −3
Melting point	41 ° C
boiling point	204 ° C
Vapor pressure	34.4 Pa (100 ° C)
solubility	Easily soluble in water (800 g · l −1 at 20 ° C) and ethanol
safety instructions
GHS hazard labeling from  Regulation (EC) No. 1272/2008 (CLP) , expanded if necessary danger H and P phrases H: 302-312-314-335 P: 261-280-305 + 351 + 338-310
Toxicological data	750 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 .

Hexamethylene diamine (HMD, HMDA) is a chemical compound from the group of aliphatic amines and an important precursor for the manufacture of polyamides .

Manufacturing

Hexamethylenediamine is produced on an industrial scale by hydrogenating adiponitrile using two different processes. In the first process, which was developed by DuPont , the hydrogenation takes place in the presence of ammonia at a high pressure of around 250 bar. The catalyst is a fixed bed made of iron. In the second process, which was developed by the company Rhodiatoce (a joint venture between Rhône-Poulenc and Montecatini ), hydrogenation is carried out at an average pressure of around 40 bar. The hydrogenation takes place without a solvent with small added amounts of alkali metal hydroxides (e.g. sodium hydroxide ) over Raney nickel catalysts in suspension.

In the laboratory, production from furfural is recommended , in which furfural is decarbonylated via a ZnO - Cr ₂ O ₃ contact . With the furan obtained , an ether cleavage (favored by the diene character) can now be carried out with HCl . After reaction with sodium cyanide and complete hydrogenation , hexamethylenediamine is also obtained.

use

Hexamethylenediamine is an intermediate for polyamides such as nylon . This plastic ( polymer ) is formed as a condensation product from adipic acid and hexamethylenediamine with elimination of water, the monomeric intermediate stage is also called AH salt after the initial letters of the components . By the reaction of hexamethylene diamine with phosgene is hexamethylene diisocyanate which as component for the production of obtained polyurethanes is used.

Through systemic studies on the reaction of lactose / lactulose with amines , it was discovered in January 2019 that hexamethylenediamine in a strongly alkaline solution (pH 13) produces a similar red color as the Wöhlk reaction and Fearon's test . The reaction with 0.025 molar hexamethylenediamine solution at 60 ° C performs significantly better in the risk assessment than the comparable processes with ammonia and methylamine. It can be used to detect 1,4-linked disaccharides (lactose, maltose , cellobiose ). The cherry-red dye has an absorption maximum at 550 nm.

Individual evidence

1. ↑ Entry on 1,6-HEXANEDIAMINE in the CosIng database of the EU Commission, accessed on February 12, 2020.
2. ↑ ^{a b c} Entry on hexane-1,6-diamine. In: Römpp Online . Georg Thieme Verlag, accessed on December 25, 2014.
3. ↑ ^{a b c d e f g h} Entry on hexamethylenediamine in the GESTIS substance database of the IFA , accessed on February 1, 2016(JavaScript required) .
4. ↑ Entry on Hexamethylenediamine 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 .
5. ↑ Klaus Ruppersberg, Horst Klemeyer: Lactose rapid test: How can you detect milk sugar in 60 seconds? In: CHEMKON . Wiley-Verlag, January 23, 2020, ISSN  0944-5846 , doi : 10.1002 / ckon.201900064 .