Disodium methyl arsonate

Structural formula
General
Surname	Disodium methyl arsonate
other names	DSMA
Molecular formula	CH 3 AsNa 2 O 3
Brief description	colorless solid
External identifiers / databases
CAS number 144-21-8 EC number 205-620-7 ECHA InfoCard 100.005.110 PubChem 8947 Wikidata Q3066717
properties
Molar mass	183.93 g mol −1
Physical state	firmly
Melting point	132-139 ° C
solubility	Easily soluble in water (279 g l −1 at 20 ° C) soluble in methanol sparingly soluble in ethanol
safety instructions
GHS labeling of hazardous substances danger H and P phrases H: 331-301-410 P: ?
Toxicological data	10000 mg kg −1 ( LD 50 ,  rabbit ,  transdermal ) 821 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 .

Disodium methyl arsonate is a chemical compound of sodium from the group of arsonates or the organic arsenic compounds . It is the disodium salt of methylarsonic acid .

Extraction and presentation

Disodium methyl arsonate can be obtained by reacting sodium arsenite with methyl iodide in the presence of alkali hydroxides such as sodium hydroxide or by reacting sodium arsenite with dimethyl sulfate .

${\displaystyle \mathrm {Na_{3}AsO_{3}+CH_{3}I\longrightarrow CH_{3}AsNa_{2}O_{3}+NaI} }$

${\displaystyle \mathrm {Na_{3}AsO_{3}+(CH_{3}O)_{2}SO_{2}\longrightarrow CH_{3}AsNa_{2}O_{3}+CH_{3}O-SO_{2}-ONa} }$

properties

Disodium methyl arsonate is a colorless solid that is easily soluble in water.

use

Disodium methyl arsonate (like sodium methyl arsenate ) is used as a herbicide (in the USA for cotton). It has also been used in veterinary medicine.

Individual evidence

1. ^ ^{A b} Christopher G. Morris, Academic Press: Academic Press Dictionary of Science and Technology . Gulf Professional Publishing, 1992, ISBN 0-12-200400-0 , pp. 659 ( limited preview in Google Book search).
2. ↑ ^{a b c d e f g} Entry on disodium methyl arsonate in the GESTIS substance database of the IFA , accessed on March 7, 2020(JavaScript required) .
3. ↑ Terry Hills: Lotus Illustrated Dictionary of Organic Chemistry . Lotus Press, 2004, ISBN 978-81-89093-51-8 , pp. 68 ( limited preview in Google Book search).
4. ↑ ^{a b c} P. H. List, L. Hörhammer: Chemicals and Drugs Part A: NQ . Springer-Verlag, 2013, ISBN 978-3-642-65035-2 , pp. 108 ( limited preview in Google Book search).
5. ↑ Land Use Effect on Arsenic Concentrations in Benton and Washington Counties . ProQuest, 2008, ISBN 0-549-66748-2 , pp. 12 ( limited preview in Google Book search).
6. ↑ Andrew D. Eaton, Hsaio Chiu Wang, Jack Northington, AWWA Research Foundation: Analytical Chemistry of Arsenic in Drinking Water . American Water Works Association, 1998, ISBN 978-0-89867-907-6 , pp. 2 ( limited preview in Google Book search).