Phosphorodithioates, dialkyl

Sulfur monochloride can act as a chlorinating agent in some reactions. For example, 0,0-diaLkyl phosphorodithioic acids [756-80-9] are converted to 0,0-diaLkylphosphorochloridothioate ... 

Reaction of 2-chloromethyl-4//-pyrido[l,2-a]pyrimidin-4-ones 385 with O.O-dialkyl phosphorothioates and phosphorodithioates in a mixture of ethanol and toluene in the presence of potassium hydroxide at 60-70°C gave insectidical or nematocidal phosphorus derivative 386 (83EUP81945). 

Batora, V. KovAc, J. The determination of small quantities of some insecticidal dialkyl phosphorodithioates in factory air. Chem. Tech. (Berlin), 1964, 16, 230. 

The reactions of potassium thiotosylate and potassium 0,0-dialkyl phospho-rodithioates with alkynyl(phenyl)iodonium salts afford good yields of alkynyl thiotosy-lates and alkynyl phosphorodithioates (equations 63 and 64)87,. Cyclopentenyl products have not been reported in either case. 

Addition of 0,0-Dialkyl Phosphorodithioates to Acetylated 1,2-Unsaturated Hexo- and Pentopyranoses General Procedure14 ... 

A novel and practical synthesis of S-(l- and 2-halogenoalkyl) sugars (43), including some at the anomeric center, has been developed. The synthesis consists of reactions of readily available S-(0,0-dialkyl)phosphorodithioates... 

OO-Dialkyl hydrogen phosphorodithioates react more readily with dialkylcyana-mides than with alkyl cyanides, but the nature of the products is dependent upon the... 

The readily available OO-dialkyl phosphorodithioic acids (13) are converted into the corresponding phosphorothioic acids by reaction with nitriles in the presence of limited amounts of waterX In view of the initial difficulty encountered in preparing the sulphur analogue, the simple synthesis of the selenopyrophosphate ester (14) from selenious acid and the cyclic phosphonate (15) is remarkableX ... 

An important starting material in the preparation of phosphorus esters containing two sulfur atoms is phosphorus pentasuliide (6), formed by the reaction of phosphorus and sulfur at high temperature. Reaction in an anhydrous medium with alcohols gives 0,0-dialkyl phosphorodithioates with evolution of hydrogen sulfide (Christmann, 1928 Malatesta and Pizzotti, 1945). 

Dialkyl phosphorothiochloridates, mentioned earlier, can be prepared by chlorination of 0,0-dialkyl phosphorodithioates (Hechenbleikner, 1947 1949). 

The salts of 0,0-dialkyl phosphorodithioates can also be alkylated to form 0,0,S-trialkyl phosphorodithioates. This reaction is used in the preparation of several important insecticides. 

Cassaday c/ al. (1948) prepared several S-carbamoylmethyl phosphorodithioates by the reaction of the salts of 0,0-dialkyl phosphorodithioic acids with various N-substituted chloroacetamides, and investigated their biological properties. Of these, practical importance has been attained by O.O-dimethyl-S-(N-methylcarbamoyl)-methyl phosphorodithioate, known by the name dimethoate (85). 

Cassaday (1950), Shostakovski et al. (1951) and Melnikov et al. (1952) investigated extensively the addition reactions of dialkyl phosphorodithioic acids to unsaturated dicarbonic acid esters, and found that the dialkyl phosphorodithioic acids are added at the double bond in the same way as are mercaptans. This reaction was used by Cassaday (1950) who prepared 0,0-dimethyl-S-(l,2-dicarbethoxy)-ethyl phosphorodithioate by the addition reaction of dimethyl phosphorodithioic acid and maleic acid diethyl ester. This compound, known by the name malathion (89), became one of the most important phosphorus ester insecticides because of its low toxicity to warm-blooded animals. 

On investigating the relationship between the action and structure of the compounds, Kado (1969) established that S-benzyl-0,0-dialkyl derivatives are more effective than the respective O-benzyl-phosphate, phosphorothioate and phosphorodithioate derivatives. The 0,0-diisopropyl derivative is more stable than the diethyl derivative and at the same time less toxic to warm-blooded organism (Yamamoto et al., 1973). Recently, 15000 tons of the diisopropyl derivative (IBP), marketed under the name Kitazin P , has been used in Japan for prevention of rice blast (Searle et al., 1973). 

Zinc phosphorodithioate esters were originally incorporated in automobile engine oils as antioxidants, and their usefulness as antiwear and antiscuffing additives was discovered by experience in service. For antioxidant service it was found that dialkyl esters of chain length in the range were the most useful, and practical experience with an-... 

Investigations of the behavior of metal salts of phosphorodithioate esters along chemical lines have given rise to a number of proposed mechanisms for the action of these substances as lubricant additives. The views of Baumgarten [53] are quite explicit a chemisorbed monomolecular film of zinc dialkyl dithiophosphate is quickly es-... 

It is known from practical experience that in general metal salts of phosphorodithioic diesters, particularly the zinc dialkyl dithiophos-phates, are effective antiwear and antiscuff additives, but systematic data relating chemical structure with additive performance are rather... 

In common with simple thiols and (9, (9-dialkyl phosphorodithioates, phosphinodithioic acids add to alkenes according to the Markovnikoff rule (propenenitrile is a possible exception to this behaviour) and even in the absence of a catalyst (equation 44). In the presence of sodium methoxide, anti-Markovnikoff behaviour is often observed as the result of Michael addition of the acid anion (equation 45). Addition of the acids to otherwise saturated nitriles leads, following acidolysis of intermediate species, to thiocarboxamides and the phosphinothioyl halide (Scheme. 50). 

Si) or their tin analogues (equation 5 Z = Sn) yield 6>,(7-dialkyl phosphorodithioate... 

Reaction of dialkyl phosphorodithioic acids with a halo compound in the presence of PTC and alkali... 

Phosphoric acid, triphenyl ester. See Triphenyl phosphate Phosphoric acid, tris (2-ethylhexyl) ester. See Trioctyl phosphate Phosphoric acid, tris (methylphenyl) ester Phosphoric acid, tritolyl ester. See Tricresyl phosphate Phosphoric acid, zinc salt (2 3). See Zinc phosphate Phosphorodithioic acid, mixed 0,0-bis (iso-butyl and pentyl) esters, zinc salt. See Zinc dialkyl dithiophosphate Phosphorous acid, cyclic neopentanetetrayl bis (2,4-di-t-butylphenyl) ester. See Bis (2,4-di-t-butylphenyl) pentaerythritol diphosphite Phosphorous acid, triisooctyl ester. See Triisooctyl phosphite Phosphorous acid triphenyl ester. See Triphenyl phosphite... 

Phosphorodithioic acid, mixed 0,0-bis (isobutyl and pentyl) esters, zinc salt. See Zinc dialkyl dithiophosphate Phosphorofluoridic acid, calcium salt. See Calcium monofluorophosphate Phosphorofluoridic acid, disodium salt. See Sodium fluorophosphate (Na2P03p) Phosphorofluoridic acid, monoammonium salt. See Ammonium monofluorophosphate Phosphorofluoridic acid, potassium salt. See Potassium monofluorophosphate Phosphorothioic acid. See Diazinon Phosphorothioic acid, S-((6-chloro-2-oxooxazxolo(4,5-b) pyridin-3(2H)-yl)methyl) 0,0-dimethyl ester. See Azamethiphos, Phosphorothioic acid, 0-(2,5-dichloro-4-iodophenyl) 0,0-dimethyl ester. See lodofenphos... 

Various polysulphides of types (9.507) are known. Treatment of dialkyl phosphorodithioic or dialkyl phosphorothiolic acids with H2O2, Brj or I2 results in the formation of a P-S-S-P chain. Longer chains result from using SCI2 or S2CI2 (9.508). Other methods of synthesis are represented by (9.509) through (9.511). 

Phosphorodithioic acid 0,0 -dialkyl ester (dialkyldithiophosphoric acid)... 

Handley TM, Dean JA (1962) O, O -dialkyl phosphorodithioic acids as extractants for metals. Anal Chem 34 1312-1315... 

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