1068-22-0

Basic information

• Product Name: AMMONIUM O,O-DIETHYLDITHIOPHOSPHATE
• Synonyms: AMMONIUM O,O-DIETHYLDITHIOPHOSPHATE;AMMONIUM-O,O-DIETHYL PHOSPHORODITHIATE;AMMONIUM DIETHYLDITHIOPHOSPHATE;DIETHYL DITHIOPHOSPHATE, AMMONIUM SALT;ammonium,o,o-diethylphosphorodithioate;ammoniumethylphosphorodithioate;ammoniumo,o-diethyldiethiophosphate;nf-133
• CAS NO: 1068-22-0
• Molecular Formula: C₄H₁₁O₂PS₂*H₃N
• Molecular Weight: 203.26
• EINECS: 213-942-4
• Product Categories: Pharmaceutical Intermediates;Organic Building Blocks;Organic Phosphates/Phosphites;Phosphorus Compounds;Aliphatics;Phosphorylating and Phosphitylating Agents;Sulfur & Selenium Compounds
• Mol File: 1068-22-0.mol
• Article Data: 5

Chemical Properties

• Melting Point: 164-166 °C(lit.)
• Boiling Point: 232.7°Cat760mmHg
• Flash Point: 94.5°C
• Appearance: White/Crystalline
• Density: 1.214g/cm³
• Vapor Pressure: 0.0153mmHg at 25°C
• Refractive Index: 1.546
• Storage Temp.: ?20°C
• Water Solubility: Soluble in water, methanol, ethanol, pyridine, acetone & ammonia. Insoluble in ethyl acetate, methyl chloride and chloroform
• CAS DataBase Reference: AMMONIUM O,O-DIETHYLDITHIOPHOSPHATE(CAS DataBase Reference)
• NIST Chemistry Reference: AMMONIUM O,O-DIETHYLDITHIOPHOSPHATE(1068-22-0)
• EPA Substance Registry System: AMMONIUM O,O-DIETHYLDITHIOPHOSPHATE(1068-22-0)

Safety Data

• Hazard Codes: Xn,T,F
• Statements: 20/21/22-39/23/24/25-23/24/25-11
• Safety Statements: 36-45-36/37-16-7
• RIDADR: UN 3335
• WGK Germany: 3
• RTECS: BP8145000
• Hazardous Substances Data: 1068-22-0(Hazardous Substances Data)

Usage

Chemical Properties

white powder

Uses

Different sources of media describe the Uses of 1068-22-0 differently. You can refer to the following data:
1. O,O-Diethyl Dithiophosphate AMMoniuM Salt can be used in the synthesis of novel phosphorothioates and phosphorodithioates
2. Diethyl dithiophosphate ammonium salt can be used in the extraction of arsenic. It is used as a source of the (C2H5O)2PS2- ligand in coordination chemistry and in analytical chemistry for determination of various ions. It can be obtained by the reaction of phosphorus pentasulfide with ethanol and ammonia.

InChI:InChI=1/C4H12NO2PS2/c1-3-6-8(9,10-5)7-4-2/h3-5H2,1-2H3

Synthetic route

{Mo2(N(C6H4CH3))2(S2P(OC2H5)2)2S(O2CCH3)(SNH2)} + O,O-Diethyl hydrogen phosphorodithioate (298-06-6) → ammonium O,O-diethyldithiophosphate (1068-22-0) + {Mo2(N(C6H4CH3))2(S2P(OC2H5)2)2S(O2CCH3)(S2PS(OC2H5)2)}

Conditions	Yield
In chloroform The Mo-compd. in CHCl3 is treated with (EtO)2PS2H and stirred 30 min.; Addn. of C6H6, centrifugation and decantation left the ammonium compd., which is further rinsed three times with C6H6, each time followed by centrifugation and decantation, and then dried.;	A 87% B n/a

{Mo2(N(C6H4CH3))2(S2P(OC2H5)2)2S(O2CCH3)(SNH2)} + O,O-Diethyl hydrogen phosphorodithioate (298-06-6) → bis(diethoxyphosphoryl)disulphide (2901-90-8) + ammonium O,O-diethyldithiophosphate (1068-22-0) + {Mo(NTo)(S2P(OEt)2)(μ3-S)}4

Conditions	Yield
In chloroform-d1 byproducts: acetic acid; To the Mo-compd. in CDCl3 is added (EtO)2PS2H, causing rapid darkening.; Pptn. of colorless crystals; (31)P-NMR and (1)H-NMR spectroscopy;

tetrafluoroboric acid diethyl ether (67969-82-8) + ammonium O,O-diethyldithiophosphate (1068-22-0) + [(η(5)-indenyl)Mo(η(3)-C3H5)(CO)2] → (η(5)-indenyl)Mo(CO)2(κ(2)-S2P(OEt)) (207131-93-9)

Conditions	Yield
In dichloromethane Ar-atmosphere; stirring soln. of equimolar amts. of Mo-complex and HBF4 for 10 min, addn. of excess of (EtO)2PS2NH4, stirring for 10 h; filtration, evapn., extn. (hexane); elem. anal.;	98%

ammonium O,O-diethyldithiophosphate (1068-22-0) + zirconium(IV) chloride (10026-11-6) → Zr(S2P(OC2H5)2)4

Conditions	Yield
In dichloromethane byproducts: NH4Cl; addn. of ZrCl4 in CH2Cl2 to a suspn. of the dithiophosphate in CH2Cl2 (1:4 molar ratio) under exclusion of moisture, refluxing (constant stirring, 6 h); filtration from pptd. NH4Cl4, removal of solvent (reduced pressure), washing (n-hexane), drying; elem. anal.;	94%

ammonium O,O-diethyldithiophosphate (1068-22-0) + trichlorodimethoxymolybdenum(V) (51325-41-8) → dichlorodimethoxymolybdenum(V) O,O'-diethylthiophosphate

Conditions	Yield
In benzene byproducts: NH4Cl; exclusion of moisture, stirring equimolar amts. of trichloromethoxymolybdenum(V) and NH4S2P(OC2H5)2 for 2 h at room temp., change of colour from brown to green; filtering off pptd. NH4Cl, removing the solvent under reduced pressure at room temp., elem. anal.;	93.3%

ammonium O,O-diethyldithiophosphate (1068-22-0) + zinc(II) sulfate (7733-02-0) → bis(O,O-diethyldithiophosphato)zinc (7268-60-2, 46946-10-5)

Conditions	Yield
In water mixed; filtered; extd. (diethyl ether); dried (over MgSO4); evapd.; recrystd. (light petroleum); elem. anal.;	90%

ammonium O,O-diethyldithiophosphate (1068-22-0) + ethylphenyltin(IV) dichloride (15649-27-1) → (C2H5C6H5Sn(SSP(OC2H5)2)2) (116178-60-0)

Conditions	Yield
In hexane byproducts: NH4Cl; to a susp. of NH4SSP(OEt)2 in hexane a soln. of EtPhSnCl2 was added andthe reaction mixt. was allowed to stir for 2-3 h at room temp; NH4Cl formed during the reaction was filtered off, filtrate was concd. under vac., dissolving in anhydrous hexane, filtration through florisil under N2; elem. anal.;	90%

ammonium O,O-diethyldithiophosphate (1068-22-0) + dimethyltin dichloride (753-73-1) → (CH3)2SnCl(SSP(OC2H5)2) (116178-66-6)

Conditions	Yield
In hexane byproducts: NH4Cl; to a susp. of NH4SSP(OEt)2 in hexane a soln. of Me2SnCl2 was added in 1:1 stoich. and the reaction mixt. was allowed to stir for 2-3 h at roomtemp; NH4Cl formed during the reaction was filtered off, filtrate was concd. under vac., elem. anal.;	90%

ammonium O,O-diethyldithiophosphate (1068-22-0) + methylphenyltin(IV) dichloride (15649-26-0) → (CH3C6H5Sn(SSP(OC2H5)2)2) (116178-59-7)

Conditions	Yield
In hexane byproducts: NH4Cl; to a susp. of NH4SSP(OEt)2 in hexane a soln. of MePhSnCl2 was added andthe reaction mixt. was allowed to stir for 2-3 h at room temp; NH4Cl formed during the reaction was filtered off, filtrate was concd. under vac., dissolving in anhydrous hexane, filtration through folrisil under N2; elem. anal.;	89%

ammonium O,O-diethyldithiophosphate (1068-22-0) + (C6H5C(NOH)C(NO)C6H5)SbCl2 → Sb((C6H5)2C2N2(OH)O)(S2P(OC2H5)2)2

Conditions	Yield
In benzene byproducts: NH4Cl; moisture-free atmosphere; stirring with slight heating (45 - 50°C, 3 - 4 h); filtration, solvent removal (reduced pressure), recrystn. (benzene/petroleum ether = 1 : 1); elem. anal.;	88%

ammonium O,O-diethyldithiophosphate (1068-22-0) + MoI2(CO)3(MeCN)2 (102349-56-4) + 1,2-bis-(diphenylphosphino)ethane (1663-45-2) → Mo(CO)(S2P(OC2H5)2)2(P(C6H5)2CH2)2

Conditions	Yield
In dichloromethane byproducts: CO; MoI2(CO)3(NCMe)2 dissolved in CH2Cl2; solid NH4(S2P(OEt)2) added with stirring; after 30 min ppt. filtered off; to filtrate Ph2PCH2CH2PPh2 (ratio 1:1) added; soln. stirred for 30 min; concd.; hexane added; cooled down (-20°C) overnight; elem. anal.;	87%

ammonium O,O-diethyldithiophosphate (1068-22-0) + MoI2(CO)3(MeCN)2 (102349-56-4) + 1,2-bis-(diphenylphosphino)ethane (1663-45-2) → [Mo(CO)2(S2P(OC2H5)2)2](μ-(C6H5)2PCH2CH2P(C6H5)2)

Conditions	Yield
In dichloromethane byproducts: CO; MoI2(CO)3(NCMe)2 dissolved in CH2Cl2; solid NH4(S2P(OEt)2) added with stirring; after 30 min ppt. filtered off; to filtrate Ph2PCH2CH2PPh2 added(ratio 2:1); soln. stirred for 30 min; concd.; hexane added; cooled down (-20°C) overnight; elem. anal.;	87%

ammonium O,O-diethyldithiophosphate (1068-22-0) + [Pd(PPh3)Cl]2(μ,η2-SCNMe2)2 (79969-97-4, 581106-72-1) → [Pd(triphenylphosphine)(η1-CSNMe2)(η2-diethyldithiophosphate)] (742078-08-6)

Conditions	Yield
In CH2Cl2 under N2; Pd complex treated with NH4(S2P(OEt)2) in CH2Cl2 at ambient temp.;	87%

ammonium O,O-diethyldithiophosphate (1068-22-0) + ((Pd(μ-I)((CH2)2S(O)Me))2) → Pd{(CH2)2(SO)(CH3)}{S2P(OC2H5)2}

Conditions	Yield
In dichloromethane Addn. of org. compd. to suspn. of Pd-complex (CH2Cl2) using n-Bu4NI as phase transfer catalyst and stirring. The yellow suspn. is dissolved within 5 min.;	85%
In dichloromethane Addn. of org. compd. to suspn. of Pd-complex (CH2Cl2). After stirring of mixt. (10 min), the yellow suspn. comes into soln. and some white solid is pptd. Further stirring for 1 h.; Washing 3 times with H2O, removal of solvent, recrystn. of residue from n-hexane/CH2Cl2, elem. anal.;	63%

ammonium O,O-diethyldithiophosphate (1068-22-0) + dichlorodiethylstannane (866-55-7) → (C2H5)2SnCl(SSP(OC2H5)2) (116178-67-7)

Conditions	Yield
In hexane byproducts: NH4Cl; to a susp. of NH4SSP(OEt)2 in hexane a soln. of Et2SnCl2 was added in 1:1 stoich. and the reaction mixt. was allowed to stir for 2-3 h at roomtemp; NH4Cl formed during the reaction was filtered off, filtrate was concd. under vac., elem. anal.;	85%

ammonium O,O-diethyldithiophosphate (1068-22-0) + chlorotriphenylgermane (1626-24-0) → triphenyl(O,O'-diethyldithiophosphato)germanium (113557-04-3)

Conditions	Yield
In benzene byproducts: NH4Cl; soln. of 1.0 mmol of Ph3GeCl and C6H6 added to 1.2 mmol of dry (EtO)2PS(S)NH4 under dry N2, warmed up to 20°C, stirred for 4 h; NH4Cl filtered off, filtrate slowly evapd. in vac.; elem. anal.;	85%

ammonium O,O-diethyldithiophosphate (1068-22-0) + dibutyltin chloride (683-18-1) → dibutyltin(IV) diethyldithiophosphate (21768-68-3)

Conditions	Yield
In benzene byproducts: NH4Cl; to suspn. of ammonium diethyldithiophosphate is added dialkyltindichloride in benzene, exothermic reaction, white ppt. separates at room temp.,refluxing for 0.5 h; ppt. is filtered off, benzene is removed under reduced pressure, distn.(100-102°C/0.01 mm), elem. anal.;	85%
In benzene byproducts: NH4Cl; to suspn. of ammonium diethyldithiophosphate is added dialkyltindichloride in benzene, exothermic reaction, white ppt. separates at room temp.,refluxing for 0.5 h; ppt. is filtered off, benzene is removed under reduced pressure, distn., elem. anal.;	80%

ammonium O,O-diethyldithiophosphate (1068-22-0) + cyclopentadienyltrichloromolybdenum(IV) → [Mo(η(5)-cyclopentadienyl)Cl2(O,O'-diethyldithiophosphate)] (504408-08-6)

Conditions	Yield
In dichloromethane under N2 atm. using Schlenk techniques; to suspn. of Mo complex in CH2Cl2 added org. salt at room temp.; stirred for 10 h; mixt. filtered; filtrate concd. to dryness; residue washed (Et2O); elem.anal.;	85%

ammonium O,O-diethyldithiophosphate (1068-22-0) + trichloro(2,2'-bipyridine)ruthenium (69141-04-4) → Ru((C5H4N)2)(SP(S)(OC2H5)2)2 (220229-56-1)

Conditions	Yield
In methanol elem. anal.;	85%

ammonium O,O-diethyldithiophosphate (1068-22-0) + di[(7,8-benzoquinolyl)(μ-hydroxo)palladium(II)] → (O,O'-diethyldithiophosphate)(7,8-benzoquinolyl)palladium(II)

Conditions	Yield
In dichloromethane suspn. of Pd complex and protic ligand (1:2) in CH2Cl2 stirred at room temp. for 30 min; concd.(vac.), pptd.(Et2O), filtered, washed (H2O, Et2O), dried (air), recrystd.(CH2Cl2/Et2O), elem. anal.;	84%

ammonium O,O-diethyldithiophosphate (1068-22-0) + MoI2(CO)3(MeCN)2 (102349-56-4) + triphenylphosphine (603-35-0) → Mo(CO)2(S2P(OC2H5)2)2(P(C6H5)3) (63339-43-5)

Conditions	Yield
In dichloromethane byproducts: CO; MoI2(CO)3(NCMe)2 dissolved in CH2Cl2; solid NH4(S2P(OEt)2) added with stirring; after 30 min ppt. filtered off; to filtrate PPh3 added; soln. stirred for 30 min; concd.; hexane added; cooled down (-20°C) overnight; elem. anal.;	83%

sodium borodeuteride + ammonium O,O-diethyldithiophosphate (1068-22-0) + tetrakis(actonitrile)copper(I) hexafluorophosphate (64443-05-6) → [Cu4(μ4-D)(μ3-Cu)4(S2P(O(i)Pr)2)6](PF6)*5H2O

Conditions	Yield
In tetrahydrofuran under inert atm. soln. Cu(MeCN)4PF6, NH4(S2P(O-i-Pr)2), and NaBD4 in THFwere stirred at room temp. for 30 min; soln. was filtered and evapd. to dryness in vacuo, residue was washed with water and dried in vacuo; elem. anal.;	83%

ammonium O,O-diethyldithiophosphate (1068-22-0) + tetrakis(actonitrile)copper(I) hexafluorophosphate (64443-05-6) → [Cu8(S2P(OEt)2)6](PF6)2

Conditions	Yield
In acetone byproducts: NH4PF6; under inert atm. soln. Cu(MeCN)4PF6 and NH4(S2P(OEt)2) in acetone was stirred at room temp. for 1 h; soln. was filtered and evapd. to dryness in vacuo, residue was washed with water; elem. anal.;	83%

ammonium O,O-diethyldithiophosphate (1068-22-0) + diphenyltin(IV) dichloride (1135-99-5) → (C6H5)2SnCl(SSP(OC2H5)2) (116178-70-2)

Conditions	Yield
In hexane byproducts: NH4Cl; to a susp. of NH4SSP(OEt)2 in hexane a soln. of Ph2SnCl2 was added in 1:1 stoich. and the reaction mixt. was allowed to stir for 2-3 h at roomtemp; NH4Cl formed during the reaction was filtered off, filtrate was concd. under vac., elem. anal.;	82%

copper(ll) sulfate pentahydrate + ammonium O,O-diethyldithiophosphate (1068-22-0) → copper(I) diethyldithiophosphate

Conditions	Yield
In water A soln. of CuSO4 in H2O was added NH4S2P(OR)2 in H2O; brown ppt. was extd. with CH2Cl2, evapd., MeOH was added;; ppt. was recrystd. from CH2Cl2-C6H5CH3; elem. anal.;;	82%

ammonium O,O-diethyldithiophosphate (1068-22-0) + dichlorodimethylgermanium (1529-48-2) → dimethylbis(O,O'-diethyldithiophosphato)germanium (113557-02-1)

Conditions	Yield
In benzene byproducts: NH4Cl; soln. of 1.3 mmol of Me2GeCl2 and C6H6 added to 2.8 mmol of dry (EtO)2PS(S)NH4 occasionally cooled to -10°C under dry N2, warmed up to 10°C, stirred for 4 h; NH4Cl filtered off, filtrate slowly evapd. in vac.; elem. anal.;	82%

ammonium O,O-diethyldithiophosphate (1068-22-0) + [W(acetonitrile)2(η3-allyl)(CO)2Br] (62651-74-5) → [W(acetonitrile)(η3-allyl)(CO)2(η2-diethyldithiophosphato)] (520505-25-3)

Conditions	Yield
In dichloromethane under N2; CH2Cl2 added to equimolar mixt. of W complex and ligand at ambient temp.; stirred for 10 min; solvent removed in vac.; abstracted with Et2O; n-hexane added; filtered;ppt. washed with cold n-hexane; dried in vac.; recrystd. from cold n-he xane-Et2O; elem. anal.;	82%

tetrahydrofuran (109-99-9) + sodium tetrahydroborate (16940-66-2) + ammonium O,O-diethyldithiophosphate (1068-22-0) + tetrakis(actonitrile)copper(I) hexafluorophosphate (64443-05-6) → [Cu4(μ4-H)(μ3-Cu)4(S2P(OEt)2)6](PF6)*0.5THF

Conditions	Yield
In tetrahydrofuran under inert atm. soln. Cu(MeCN)4PF6, NH4(S2P(OEt)2), and NaBH4 in THF were stirred at room temp. for 30 min; soln. was filtered and evapd. to dryness in vacuo, residue was washed with water and dried in vacuo; elem. anal.;	82%

ammonium O,O-diethyldithiophosphate (1068-22-0) + dichloro(pentamethylcyclopentadienyl)rhodium (III) dimer → (C5(CH3)5)RhCl(S2P(OC2H5)2) (243845-44-5)

Conditions	Yield
In dichloromethane byproducts: NH4Cl; N2-atmosphere; stoich. amts., stirring (room temp., 3 h); filtration off of NH4Cl, concn. (vac.), recrystn. (CH2Cl2/hexane); elem. anal.;	81%

ammonium O,O-diethyldithiophosphate (1068-22-0) + MoI2(CO)3(MeCN)2 (102349-56-4) + 1,2-bis-(diphenylphosphino)ethane (1663-45-2) → MoI(CO)2((C6H5)2PCH2)2(S2P(OC2H5)2) (404579-79-9)

Conditions	Yield
In dichloromethane MoI2(CO)3(NCMe)2 dissolved in CH2Cl2; NH4(S2P(OEt)2) added with stirring; after 30 min mixt. filtered; Ph2PCH2CH2PPh2 added to filtrate; soln. stirred for 30 min; hexane added; mixt. kept at 0.°C for 3 ds; elem. anal.;	81%

sodium tetrahydroborate (16940-66-2) + ammonium O,O-diethyldithiophosphate (1068-22-0) + tetrakis(acetonitrile)copper(I) hexafluorophosphate → 6C4H10O2PS2(1-)*7Cu(1+)*H(1-)

Conditions	Yield
In chloroform at 20℃; for 1h; Inert atmosphere; Schlenk technique;	81%

Upstream product

• 298-06-6 O,O-Diethyl hydrogen phosphorodithioate 
• 64-17-5 ethanol 
• 79227-42-2 mixed thioanhydride of O,O-diethyl hydrogen phosphorodithioate and ethylphenylphosphinothious acid 
• 75-08-1 ethanethiol 

Downstream Products

• 24934-91-6 chlormephos 
• 3277-98-3 Dithiophosphoric acid O,O'-diethyl ester S-[(ethyl-phenyl-carbamoyl)-methyl] ester 
• 64212-85-7 Thiophosphoric acid S-{[(4-chloro-phenyl)-methyl-carbamoyl]-methyl} ester O,O'-diethyl ester 
• 947-34-2 O,O-diethyl S-phenyl phosphorodithioate 
• 953-33-3 O,O-diethyl S-(4-chlorophenyl) phosphorodithioate 
• 79359-70-9 O,O-diethyl S-(3-oxo-1,3-diphenylpropyl)phosphorodithioate 
• 1374576-43-8 O,O-diethyl S-(3-oxo-3-phenylpropyl)phosphorodithioate 
• 1034024-74-2 S,S'-(1,2-phenylenedimethylene)-O,O,O',O',-tetraethyl phosphorodithioate 
• 1012320-15-8 [Pd(η2-diethyldithiophosphate)]2(μ-bis(diphenylphosphino)amine(-1H))(μ-SCNMe2) 
• 742078-08-6 [Pd(triphenylphosphine)(η1-CSNMe2)(η2-diethyldithiophosphate)] 
• 1173818-90-0 [Ag₄(1,1-bis(diphenylphosphino)methane)2(S₂P(OEt)2)4] 
• 872971-00-1 [Cu₃(bis(diphenylphosphino)methane)3(S₂P(OEt)2)2](PF₆) 

Relevant articles and documents

Characterization of Dialkyldithiophosphates as Slow Hydrogen Sulfide Releasing Chemicals and Their Effect on the Growth of Maize

Hydrogen sulfide is a key gasotransmitter for plants and has been shown to greatly increase their growth and survival in the presence of environmental stressors. Current methods for slowly releasing hydrogen sulfide use chemicals, such as GYY-4137, but these result in the release of chemicals not found in the environment, and chemicals used may lack structures that can be readily tuned to affect the rate of release of hydrogen sulfide. In this article, we describe the synthesis and slow release of hydrogen sulfide from dialkyldithiophosphates, which are a new set of hydrogen sulfide releasing chemicals that can be used in agriculture. The rates of hydrolysis of dibutyldithiophosphate and GYY-4137 were measured in water at 85 °C and compared with each other to investigate their differences. GYY-4137 is widely used as a chemical that slowly releases H2S, but its rate of release was not previously quantified. The release of hydrogen sulfide in water at room temperature was measured for a series of dialkyldithiophosphates using a hydrogen sulfide electrode. It was shown that the structure of the dialkyldithiophosphate affected the amount of hydrogen sulfide released. The final degradation products of dibutyldithiophosphate were shown to be phosphoric acid and butanol, which are chemicals found in the environment. This result was notable because it demonstrated that dialkyldithiophosphates degrade to safe, natural chemicals that will not pollute the environment. To demonstrate that dialkyldithiophosphates have potential applications in agriculture, maize was grown for 4.5 weeks after exposure to 1-200 mg of dibutyldithiophosphate, and the weight of corn plants increased by up to 39% at low loadings of dibutyldithiophosphate.

A convenient synthesis of phosphorodithioates and novel conversion of epoxides to thiiranes

Alumina-supported ammonium acetate under microwave irradiation was found to be an efficient reagent for the preparation of phosphorodithioates from phosphorus pentasulfide under solvent-free condition. A simple, efficient, and new method has been developed for the synthesis of thiiranes from epoxides through a one-pot reaction of epoxides with the mixture of phosphorus pentasulfide in the presence of ammonium acetate and acidic alumina under reflux in EtOH or solvent-free conditions under microwave irradiation. These methods are easy, rapid, and good-yielding reactions for the synthesis of phosphorodithioates and thiiranes.

CLEAVAGE OF THE P-S BOND IN THIO DERIVATIVES OF PHOSPHORUS(III) ACIDS UNDER THE ACTION OF PHOSPHORODITHIOIC ACID ESTERS

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