2-chloropropionic acid

Structural formula
( R ) shape (left) and ( S ) shape (right)
General
Surname	2-chloropropionic acid
other names	α-chloropropionic acid
Molecular formula	C 3 H 5 ClO 2
Brief description	colorless to yellowish, almost odorless liquid
External identifiers / databases
CAS number 598-78-7 [(±) -α-chloropropionic acid] 29617-66-1 [( S ) -2-chloropropionic acid] 16987-02-3 [(±) -α-chloropropionic acid, sodium salt ] 74533-11-2 [ L - (-) - α-chloropropionic acid, sodium salt] EC number 209-952-3 ECHA InfoCard 100.009.049 PubChem 11734 ChemSpider 11241 Wikidata Q209361
properties
Molar mass	108.52 g mol −1
Physical state	liquid
density	1.26 g cm −3
Melting point	−12 ° C
boiling point	186 ° C
Vapor pressure	0.31 mbar (20 ° C)
pK s value	2.8
solubility	miscible with water miscible with all common solvents
Refractive index	1.4380 (20 ° C)
safety instructions
GHS hazard labeling from  Regulation (EC) No. 1272/2008 (CLP) , expanded if necessary danger H and P phrases H: 302-314 P: 280-305 + 351 + 338-310
Toxicological data	535–800 mg kg −1 ( LD 50 ,  rat ,  oral )
Thermodynamic properties
ΔH f 0	−522.5 kJ / mol
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

2-chloropropionic acid is a chemical compound from the group of propionic acid derivatives .

If "2-chloropropionic acid" is mentioned in this text or in the scientific literature without any additional name ( prefix ), racemic 2-chloropropionic acid is [synonyms: DL -2-chloropropionic acid, (±) -2-chloropropionic acid and ( RS ) -2 -Chlorpropionic acid] means a 1: 1 mixture of the two enantiomers .

Extraction and presentation

2-Chloropropionic acid can be obtained by chlorinating propionic acid with PCl ₃ , S ₂ Cl ₂ or chlorosulfonic acid. The L - enantiomer is made from D - lactic acid and thionyl chloride .

properties

2-chloropropionic acid is a colorless to yellowish, almost odorless liquid. Above 60 ° C it begins to decompose, producing hydrogen chloride , carbon monoxide and carbon dioxide .

use

2-chloropropionic acid is used in the manufacture of dyes, medicines and herbicides . The phenoxypropionic acid derivatives such as clodinafop , fenoxaprop , fluazifop , haloxyfop , isoxapyrifop , quizalofop and phenoxycarboxylic acids dichlorprop , fenoprop , flamprop , mecoprop and acetylalanine benalaxyl be illustrated starting from 2-chloropropionic acid.

The reduction of ( S ) -2-chloropropionic acid with lithium aluminum hydride gives ( S ) -2-chloropropanol, the simplest chlorine alcohol, which further reacts with potassium hydroxide to ( R ) - methyl oxirane .

Related links

• 3-chloropropionic acid

Individual evidence

1. ↑ ^{a b c d e f g h i} Entry on 2-chloropropionic acid in the GESTIS substance database of the IFA , accessed on February 1, 2016(JavaScript required) .
2. ↑ Bernd Engels, Carsten jewelry, Tanja Schirmeister, Reinhold Fink: Chemistry for medical professionals . Pearson Deutschland GmbH, 2008, ISBN 3-8273-7286-0 , p. 553 ( limited preview in Google Book search).
3. ↑ ^{a b c} Toxicological assessment of α-chloropropionic acid and sodium α-chloropropionate (PDF) at the professional association for raw materials and chemical industry (BG RCI), accessed on August 22, 2012.
4. ↑ 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. 3-112.
5. ↑ Entry on 2-chloropropionic acid 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 .
6. ↑ David R. Lide (Ed.): CRC Handbook of Chemistry and Physics . 90th edition. (Internet version: 2010), CRC Press / Taylor and Francis, Boca Raton, FL, Standard Thermodynamic Properties of Chemical Substances, pp. 5-23.
7. ↑ Thomas A. Unger: Pesticide Synthesis Handbook . William Andrew, 1996, ISBN 0-8155-1853-6 , pp. 1030 ( limited preview in Google Book search).
8. ↑ Koppenhoefer, B. and Schurig, V .: (R) -Alkyloxiranes of High Enantiomeric Purity from (S) -2-Chloroalkanoic Acids via (S) -2-Chloro-1-Alkanols: (R) -Methyloxiranes In: Organic Syntheses . 66, 1988, p. 160, doi : 10.15227 / orgsyn.066.0160 ; Coll. Vol. 8, 1993, p. 434 ( PDF ).