124-65-2

Basic information

• Product Name: Sodium cacodylate 97+
• Synonyms: DIMETHYLARSINIC ACID SODIUM SALT;CACODYLATE BUFFER;CACODYLATE BUFFER (PH 7.4);CACODYLIC ACID SODIUM SALT;((dimethylarsino)oxy)-sodiuas-oxide;((dimethylarsino)oxy)sodium-as-oxide;((dimethylarsino)oxy)sodiumas-oxide;alkarsodyl
• CAS NO: 124-65-2
• Molecular Formula: C₂H₆AsO₂*Na
• Molecular Weight: 159.98
• EINECS: 204-708-2
• Product Categories: Organometallics;inorganic compound
• Mol File: 124-65-2.mol
• Article Data: 0

Chemical Properties

• Melting Point: 200°C
• Boiling Point: 200°C
• Flash Point: 109.4 °C
• Appearance: /solid
• Storage Temp.: Store at RT.
• Solubility: H2O: 0.5 M at 20 °C, clear, colorless
• Stability: Stable.
• CAS DataBase Reference: Sodium cacodylate 97+(CAS DataBase Reference)
• NIST Chemistry Reference: Sodium cacodylate 97+(124-65-2)
• EPA Substance Registry System: Sodium cacodylate 97+(124-65-2)

Safety Data

• Hazard Codes: T,N
• Statements: 23/25-50/53
• Safety Statements: 20/21-28-45-60-61
• RIDADR: UN 1688 6.1/PG 2
• WGK Germany: 3
• RTECS: CH7890000
• F: 3
• HazardClass: 6.1(a)
• PackingGroup: II
• Hazardous Substances Data: 124-65-2(Hazardous Substances Data)

Usage

Chemical Properties

Different sources of media describe the Chemical Properties of 124-65-2 differently. You can refer to the following data:
1. White crystalline powder
2. Sodium cacodylate is a white crystalline solid which occurs as the trihydrate. It liquefies in the water of hydration @ 60°C and becomes anhydrous @ 120°C.

Uses

Herbicide.

Definition

ChEBI: The organic sodium salt of dimethylarsinate.

General Description

A white crystalline or granular solid with a slight odor. Toxic by ingestion, inhalation, and skin absorption. Used as a herbicide.

Air & Water Reactions

Soluble in water.

Reactivity Profile

Sodium cacodylate 97+ gives basic solutions in water. Corrodes common metals, but reaction is not hazardous. [USCG, 1999]. Liquefies in its own water of crystallization when heated to 60°C; becomes anhydrous at 120°C [Merck]. Burns with a bluish flame, emitting a garlic-like odor [Merck].

Hazard

Toxic by inhalation and ingestion.

Health Hazard

Moderately toxic; probable oral lethal dose in humans is 0.5-5 g/kg or between 1 ounce and 1 pint (or 1 lb.) for a 70 kg (150 lb.) person. It may cause disturbances of the blood, kidneys, and nervous system.

Fire Hazard

Poisoning potential is high when heated to decomposition, or on contact with acids or acid fumes, because Sodium cacodylate 97+ emits highly toxic fumes of arsenic. Avoid water solution in contact with active metals (iron, aluminum, zinc).

Agricultural Uses

Herbicide, Rodenticide, Defoliant, Veterinary medicine: This material has been used as a non-selective herbicide and defoliant for general weed control. Severely restricted for use in EU countries. Not registered for use in the U.S. There are 47 global suppliers

Trade name

ACME? Sodium cacodylate; ALKARSODYL?; ANSAR 160?; ARSECODILE?; ARSYCODILE?; BOLLS-EYE?; CHEMAID?; DREXEL EZY-PICKIN COTTON DEFOLIANT?; DREXEL KACK HERBICIDE?; DUTCH-TREAT?; HERB-ALL?; PHYTAR 560? (with Cacodylic acid); RAD-E-CATE?; SILVISAR?

Potential Exposure

This material has been used as a nonselective herbicide and for general weed control.

Shipping

UN1688 Sodium cacodylate Hazard Class: 6.1; Labels: 6.1-Poisonous materials. UN3465 Organoarsenic compound, solid, n.o.s., Hazard Class: 6.1; Labels: 6.1Poisonous materials, Technical Name Required

Purification Methods

Recrystallise it from aqueous EtOH. [Beilstein 4 H I 612.]

Incompatibilities

Incompatible with oxidizers, strong bases; acids, active metals (iron, aluminum, zinc). Contact with acids react to form highly toxic dimethylarsine gas. Attacks some metals.

Waste Disposal

For cacodylic acid, precipitate as calcium arsenate and calcium arsenite by treatment with excess lime water. Recycle if possible. If not, put in secure storage for possible disposal in leach-proof dumps. In accordance with 40CFR165, follow recommendations for the disposal of pesticides and pesticide containers. Must be disposed properly by following package label directions or by contacting your local or federal environmental control agency, or by contacting your regional EPA office.

InChI:InChI=1/C2H7AsO2.Na/c1-3(2,4)5;/h1-2H3,(H,4,5);/q;+1

Synthetic route

methylarsine oxide (593-58-8) + methyl iodide (74-88-4) → sodium cacodylate (124-65-2)

Conditions	Yield
With methanol; sodium hydroxide

diphenylantimony(V) bromide oxide (102829-02-7) + sodium cacodylate (124-65-2) → [(Sb(C6H5)2)2(O)2(O2As(CH3)2)2] (196503-04-5)

Conditions	Yield
In dichloromethane reflux (24 h); filtration, removal of solvent, crystn. (CHCl3/hexane); elem. anal.;	86%

molybdic acid + dihydrogen peroxide (7722-84-1) + sodium cacodylate (124-65-2) + tetramethlyammonium chloride (75-57-0) → N(CH3)4(1+)*(MoO(O2)2)2O2As(CH3)2(1-) = [N(CH3)4][(MoO(O2)2)2O2As(CH3)2]

Conditions	Yield
In ethanol; water stirring MoO3*H2O in aq. H2O2 at 30°C until a soln. was obtained,addn. of NaO2AsMe2 in EtOH at room temp. followed by addn. of (Me4N)Cl in H2O; addn. of EtOH, cooling to 4°C, filtration, washing (cold EtOH; Et2O), drying in air; elem. anal.;	85%

thallium(III) acetate + sodium cacodylate (124-65-2) → tris(dimethylarsinato)thallium

Conditions	Yield
In methanol at 20℃; for 3h; Darkness;	82%

sodium cacodylate (124-65-2) + μ-oxo-bis[bromotriphenylantimony(V)] (1538-64-3) → [(Sb(C6H5)3)2(O)(O2As(CH3)2)2] (196503-09-0)

Conditions	Yield
In dichloromethane reflux (20 h); filtration, removal of solvent (vac.), dissoln. (CHCl3), diffusion of hexane into the soln.; elem. anal.;	74%

molybdic acid + tetrabutyl-ammonium chloride (1112-67-0) + dihydrogen peroxide (7722-84-1) + sodium cacodylate (124-65-2) → N(C4H9)4(1+)*(MoO(O2)2)2O2As(CH3)2(1-) = [N(C4H9)4][(MoO(O2)2)2O2As(CH3)2]

Conditions	Yield
In ethanol; water stirring MoO3*H2O in aq. H2O2 at 30°C until a soln. was obtained,addn. of NaO2AsMe2 in EtOH at room temp. followed by addn. of (n-Bu4N)C l in H2O; addn. of EtOH, cooling to 4°C, filtration, washing (cold EtOH; Et2O), drying in air; elem. anal.;	60%

zinc perchlorate + sodium cacodylate (124-65-2) + N,N-bis[2-(4,5-dimethyl)benzimidazolylmethyl]-N',N'-bis(2-pyridylmethyl)-1,3-diamino-2-propanol (452295-73-7) → [[Zn2(N,N-bis[(5,6-dimethyl)benzimidazolylmethyl]-N',N'-bis(2-pyridylmethyl)-1,3-diamino-2-propanolate](O2AsMe2)](ClO4)2*H2O

Conditions	Yield
In water; acetonitrile 2 equiv. of aq. Zn-salt soln. and 1 equiv. of aq. As-compd. soln. were added to MeCN soln. of N-base; crystn. by diffusion of Et2O into the soln. for 4 d, elem. anal.;	55%

water (7732-18-5) + palladium diacetate (3375-31-3) + sodium cacodylate (124-65-2) → Pd16O24(OH)8(24-)*8C2H6As(3+)*1.25Na(1+)*0.25C2H3O2(1-)*C2H6AsO2(1-)*19H2O

Conditions	Yield
Stage #1: palladium diacetate; sodium cacodylate In aq. buffer at 20℃; for 48h; pH=7; Stage #2: water	3%

sodium cacodylate (124-65-2) → Dimethyldiselenoarsinsaeure

Conditions	Yield
With hydrogen selenide In ethanol

sodium cacodylate (124-65-2) + sulfur dioxide → bis-{dimethylarsenic}-oxide (503-80-0)

GLUTATHIONE (70-18-8) + sodium cacodylate (124-65-2) → Darinaparsin

Conditions	Yield
In water at 37℃; for 1h;

chromium(III) nitrate hexahydrate + sodium cacodylate (124-65-2) → {Cr(CH3)2AsO2(H2O)(n)}(2+)

Conditions	Yield
In water formation in aq. soln. of (Cr(H2O)6)(NO3)3 and Na cacodylate (molar ratio 1:1);; not isolated;;

chromium(III) nitrate hexahydrate + sodium cacodylate (124-65-2) → {Cr((CH3)2AsO2)2(H2O)(m)}(1+)

Conditions	Yield
In water formation in aq. soln. of (Cr(H2O)6)(NO3)3 and Na-cacodylate (molar ratio 1:2);; not isolated;;

trimethylaluminum (75-24-1) + sodium cacodylate (124-65-2) → 2As(CH3)4(1+)*[(CH3)2AlOAl(CH3)3]2(2-)=[As(CH3)4]2[(CH3)2AlOAl(CH3)3]2

Conditions	Yield
In benzene room temp.; crystn. (several weeks);

methanol (67-56-1) + iron(III) perchlorate nonahydrate + N,N,N',N'-tetrakis(2-benzimidazolylmethyl)-1,3-diamino-2-propanol + sodium cacodylate (124-65-2) → [Fe2(N,N,N',N'-tetrakis(2-benzimidazolylmethyl)-1,3-diamino-2-propanolate)(μ-dimethylarsinato)(methanolate)(methanol)](ClO4)3*5methanol*2H2O

Conditions	Yield
In methanol; ethanol elem. anal.;

methanol (67-56-1) + iron(III) perchlorate nonahydrate + sodium cacodylate (124-65-2) + iron(III) chloride (7705-08-0) + N,N,N′,N′-tetrakis(2-benzimidazolylmethyl)-2-hydroxo-1,3-diaminopropane (83144-89-2) → (C7N2H5CH2)2NCH2CH(O)CH2N(CH2C7N2H5)2Fe2Cl(H2O)O2As(CH3)2(3+)*3ClO4(1-)*5CH3OH*H2O

Conditions	Yield
In methanol; acetonitrile

iron(III) perchlorate nonahydrate + N-methyl-N,N',N'-tris(2-benzimidazolylmethyl)-2-hydroxy-1,3-diaminopropane (177778-43-7) + sodium cacodylate (124-65-2) + iron(III) chloride (7705-08-0) → [Fe2(C28H30N8O)(O2As(CH3)2)Cl2(CH3OH)](2+)*2ClO4(1-)*4CH3OH=[Fe2(C28H30N8O)(O2As(CH3)2)Cl2(CH3OH)](ClO4)2*4CH3OH

Conditions	Yield
In methanol equimolar amts. of perchlorate, chloride and arsinate; crystn. (several days);

sodium molybdate dihydrate (7631-95-0) + cesium chloride + sodium cacodylate (124-65-2) → 2Cs(1+)*H(1+)*(CH3)2AsMo4O15(3-)=Cs2((CH3)2AsMo4O15H)

Conditions	Yield
With perchloric acid In water aq. solns. of Me2AsO2Na and Na2MoO4*2H2O mixed; pH ajusted to 4.0 by adnn. of HClO4; aq. soln. of CsCl added; ppt. filtered off, washed with cold H2O, dried in air; elem. anal.;

sodium molybdate dihydrate (7631-95-0) + sodium cacodylate (124-65-2) → 2Na(1+)*H(1+)*(CH3)2AsMo4O15(3-)=Na2((CH3)2AsMo4O15H)

Conditions	Yield
With perchloric acid In water aq. solns. of Me2AsO2Na and Na2MoO4*2H2O mixed, pH adjusted to 4.0 by addn. of HClO4; concd.; ppt. isolated;

methanol (67-56-1) + sodium cacodylate (124-65-2) + diphenyltin(IV) dichloride (1135-99-5) → [Ph(Cl)Sn(O2AsMe2)(μ-OMe)]2 (1140968-31-5)

Conditions	Yield
In methanol byproducts: NaCl, C6H6; 1 equiv. of As-compd. in MeOH added to soln. of Sn-compd. in MeOH at ambient temp.; soln. filtered after a week, filtrate stored in an open flask at ambienttemp. for 9 d, crystals filtered off;

Upstream product

• 593-58-8 methylarsine oxide 
• 74-88-4 methyl iodide 

Downstream Products

• 593-57-7 dimethylarsine 
• 471-35-2 tetramethyldiarsine 
• 69819-86-9 Darinaparsin 
• 196503-09-0 [(Sb(C₆H₅)3)2(O)(O₂As(CH₃)2)2] 
• 1140968-31-5 [Ph(Cl)Sn(O2AsMe2)(μ-OMe)]2 
• 676-75-5 dimethyliodoarsine