Dichloroacetaldehyde

Structural formula
General
Surname	Dichloroacetaldehyde
other names	2,2-dichloroacetaldehyde
Molecular formula	C 2 H 2 Cl 2 O
Brief description	colorless liquid
External identifiers / databases
CAS number 79-02-7 16086-14-9 (monohydrate) EC number 201-169-5 ECHA InfoCard 100.001.063 PubChem 6576 Wikidata Q16661162
properties
Molar mass	112.94 g mol −1
Physical state	liquid
density	1.4 g / ml
Melting point	−50 ° C
boiling point	88 ° C
Vapor pressure	67 mbar (20 ° C)
solubility	easily in water (140 g l −1 at 20 ° C)
safety instructions
GHS labeling of hazardous substances H and P phrases H: 301-310 + 330-314-335-351-400 P: ?
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Dichloroacetaldehyde is a chemical compound from the group of aldehydes . It is next to the monochloroacetaldehyde and trichloroacetaldehyde one of three possible chlorinated acetaldehyde.

Extraction and presentation

Dichloroacetaldehyde, by chlorination of acetaldehyde or paraldehyde be won. The hypochlorination of 1,2-dichloroethylene using chlorine and water provides pure dichloroacetaldehyde.

properties

Dichloroacetaldehyde is a volatile liquid that is easily soluble in water, forming hydrate. In water, a diol, also known as monohydrate, chemically 2,2-dichloro-1,1-ethanediol, is formed. This compound forms colorless crystals that melt between 35 and 50 ° C and boil at 85 to 95 ° C.

The compound decomposes when heated. In the presence of Lewis acids such as antimony trichloride , iron (III) chloride , aluminum trichloride , tin (IV) chloride or boron trifluoride , the trimer hexachloroparaldehyde (2,4,6-tris (dichloromethyl) -1,3,5-trioxane) can be obtained. The trimer forms colorless crystals that melt at 131–132 ° C. At the boiling point of 210–220 ° C, dichloroacetaldehyde slowly regresses.

use

Dichloroacetaldehyde is used in the production of other chemical compounds such as mitotane . The condensation with chlorobenzene gives p , p ' -Dichloro-1,1-diphenyl-2,2-dichloroethane , which was previously used as an insecticide .

${\displaystyle \mathrm {CHCl_{2}CHO+2\,C_{6}H_{5}Cl\rightarrow CHCl_{2}CH(C_{6}H_{4}Cl)_{2}+H_{2}O} }$

safety instructions

The vapors of dichloroacetaldehyde can form an explosive mixture with air ( flash point 60 ° C).

Individual evidence

1. ↑ ^{a b c d e f g h i j} Entry on dichloroacetaldehyde in the GESTIS substance database of the IFA , accessed on January 8, 2020(JavaScript required) .
2. ↑ ^{a b c d e f} Jira, R .; Kopp, E .; McKusick, BC; Röderer, G .; Bosch, A .; Fleischmann, G .: Chloroacetaldehydes in Ullmann's Encyclopedia of Industrial Chemistry , 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim, doi : 10.1002 / 14356007.a06_527.pub2 .
3. ↑ Entry on dichloroacetaldehyde in the Hazardous Substances Data Bank , accessed on April 21, 2015.
4. ↑ Wiley-VCH: Ullmann's Fine Chemicals, 3 Volume Set: . John Wiley & Sons, 2014, ISBN 978-3-527-68359-8 , pp. 133 ( limited preview in Google Book search).