Diethyl thiophosphate

Pure parathion is a pale yellow, practically odorless oil, which crystallizes in long white needles melting at 6.0° C. (17). It is soluble in organic solvents, except kerosenes of low aromatic content, and is only slightly soluble in water (15 to 20 p.p.m. at 20° to 25° C.). Peck (35) measured its rate of hydrolysis to diethyl thiophosphate and nitro-phenate ions in alkaline solutions. He found that the reaction kinetics are first order with respect to the ester and to hydroxyl ion. In normal sulfuric acid the rate of hydrolysis was the same as in distilled water. Peck concluded that hydrolysis takes place by two mechanisms—a reaction catalyzed by hydroxyl ions and an independent uncatalyzed reaction with water. He calculated that at a pH below 10 the time for 50% hydrolysis at 25° C. is 120 days in the presence of saturated lime water the time is 8 hours. The over-all velocity constant at 25° C. is k = 0.047 [OH-] + 4 X 10-6 min.-1... 

SYNS 0,0-DIETHYL-7-HYDR0XY-3,4-TETRAMETHY-LENE COUMARINYL PHOSPHOROTHIOATE 0,0-DIETHYL-O-(7,8,9,10-TETRAHYDRO-6-OXOBENZO-(C)CHROMAN-3-YL)PHOSPHOROTHIOATE 0,0-DIETHYL-O-(7,8,9,10-TETRAHYDRO-6-OXO-6H-DIBENZO(b,d)PYRAN-3-YL)PHOSPHOROTHIOATE 0,0-DIETHYL-0-(3,4-TETRAMETHYLENE-COUMARINYL-7) THIOPHOSPHATE DITHIONE ENT 24,986 7-HYDROXY-3.4-TETRAMETHYLENE-C0UMARIN-0,0-DIETHYL THIOPHOSPHATE... 

HYDROXY-3,4-TETRAMETHYLENECOUMARIN-0,0-DIETHYL THIOPHOSPHATE see DXOOOO HYDROXYTHIOSPASMIN see HOJ150 HTOROXYTOLUENE see BDX500... 

IS0PR0PYL-4-METHYLPYRlMIDYL-0,0-DIETHYL PHOSPHOROTHIOATE see DCM750 ISOPROPYLMETHYLPYRIAnDYL DIETHYL THIOPHOSPHATE see DCM750 ISOPROPYL MYRISTATE see IQNOOO ISOPROPYL NITRATE see IQPOOO ISOPROPYL NITRILE see IJXOOO ISOPROPYL NITRITE see IQQOOO ISOPROPYL NORADRENALINE see DMA 600... 

This initial suggestion has been confirmed by the reaction between phenyl isocyanate and diethyl thiophosphate (EtO)2P(S)OH where COS has been produced [266],... 

Phosphorothioate 0,0-DiethylO-2-Isopropyl-4-Methyl-6-Pyrimidyl Thiophosphate Diethyl 2-Isopropyl-4-Methyl 6-Pyrimidyl Thionophosphate Alpha-Tox Saralex Spectracide Cherrucal Formula C]2H2iNj03PS. 

Chemical Designations - Synonyms 0,0-Diethyl 0-(p-nitrophenyl) phoshorothioate 0,0-Diethyl O-(p-nitrophenyl) thiophosphate Ethyl Parathion Phosphoroiioic acid 0,0-diethyl 0-p-nitrophenyl... 

The thiophosphate phorate is degraded in aqueous solutions at pH 8.5 to yield diethyl sulfide and formaldehyde, which are formed by nucleophilic attack either at the P = S atom or the methylene dithioketal carbon atom (Hong and Pehkonen 1998). 

The purpose of this work was to determine the toxicity to mosquito larvae of insecticide spray residues. That certain insecticides are translocated in plants (4, 5) adds impetus to this study. Fresh orchard fruit sprayed or dusted with preparations containing parathion (0,0-diethyl O-p-nitrophenyl thiophosphate), tetraethyl pyrophosphate (TEPP, HEPP), DDD [2,2-bis(p-chlorophenyl)-l,l-dichloroethane], DDT [2,2-bis(p-chlorophenyl)-l,l,l-trichloroethane], chlorinated camphene, and basic lead arsenate were shipped from California to Yonkers, N. Y., by air express for bioassay. 

The widespread commercial use of DDT [l,l,l-trichloro-2,2-bis-(p-chlorophenyl)-ethane] and the potentialities of the more recently developed parathion (0,0-diethyl O-p-nitrophenyl thiophosphate) have placed emphasis on such investigations concerning these compounds. 

Parathion (0,0-diethyl 0-p-nitrophenyl thiophosphate) is an ester of thiophosphoric acid with the empirical formula C10H14NO5PS. It is a high boiling deep-brown to yellow liquid, some samples of which possess a characteristic odor. Its boiling point has been calculated to be 375 0 C. or higher, at 760 mm. pressure its refractive index is n 5 1.15360 specific gravity is 1.26. The vapor pressure is 0.0006 mm. of mercury at 24° C. The technical grade has a purity of approximately 95%. 

Polarographic Determination of 0,0-Diethyl O-p-Nitrophenyl Thiophosphate (Parathion)... 

The 0,0-diethyl O-p-nitrophenyl thiophosphate used in the preparation of the standard curves was obtained by isolation from a high-purity technical parathion according to the method devised by Edwards and Hall (2). It was a crystalline material that melted sharply at 6° C. The physical constants were in agreement with those published by Fletcher et al. (4)-... 

A sample of 0.4863 gram of this purified 0,0-diethyl O-p-nitrophenyl thiophosphate was dissolved in acetone to make 1 liter of standard solution. A 20-ml. aliquot, containing 9.73 mg., was placed in a 100-ml. volumetric flask and 30 ml. of acetone were added. Then 0.35 gram of potassium chloride and 0.6 gram of acetic acid were dissolved in about 25 ml. of water and added to the acetone solution 0.01 g am of gelatin was dissolved in a few milliliters of water by warming, cooled, and added to the above, and the... 

The polarographic method of analysis of parathion as described here has an accuracy of = =1%, and 2 mg. of 0,0-diethyl O-p-nitrophenyl thiophosphate per 100 ml. of solution are apparently a minimum concentration for the sensitivities investigated. However, the polarograph used is equipped with resistors, so that a sensitivity of 0.003 microampere per millimeter may be used. At this sensitivity it would be possible to obtain a sufficient wave height to determine parathion at a concentration of less than 1 p.p.m. 

Diphosphitylation of 2,4-0-methylene-D-glucitol (8) with phosphorus trichloride in dioxane gave 1,3 5,6-bis- 0-(chlorophosphitc) 9 (99.5%). Its amination with diethyla-mine in benzene-diethyl ether afforded the corresponding bis-amidophosphites 10. Their reaction with sulfur afforded three P-diastereomers of cyclic thiophosphate 11 in 24.8, 4.8, and 19.5% yields (Scheme 4) [19],... 

Chemical/Physical. Hydrolyzes in water forming cis-diethyl fumarate, tra/ s-diethyl fumarate (Suffet et ah, 1967), thiomalic acid, and dimethyl thiophosphate (Mulla et al., 1981). The reported hydrolysis half-lives at pH 7.4 and temperatures of 20 and 37.5 °C were 10.5 and 1.3 d, respectively (Freed et al, 1977). In a preliminary study, Librando and Lane (1997) concluded that the hydrolysis of malathion is very sensitive to pH. At pH 8.5, <5% of the malathion remains after 2 d, whereas at pH 5.7, >90% remains after 20 d. 

Synonyms AAT AATP AC 3422 ACC 3422 AI3-15108 Alkron Aileron American Cyanamide 3422 Aphamite Aralo B 404 Bay E-605 Bayer E-605 Bladan Bladan F BRN 2059093 C-06604 Caswell No. 637 CCRIS 493 Compound 3422 Corothion Corthion Corthione Danthion DDF 0,0-Diethyl-0-4-nitrophenyl phosphorothioate 0,0-Diethyl 0-p-nitrophenyl phosphorothioate Diethyl-4-nitrophenyl phosphorothionate Diethyl-p-nitrophenyl thionophosphate 0,0-Di-ethyl-0-4-nitrophenyl thionophosphate 0,0-Diethyl-O-p-nitrophenyl thionophosphate Diethyl-p-nitrophenyl thiophosphate 0,0-Diethyl-O-p-nitrophenyl... 

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