Thiophosphoric acid

Presumably intermediate thiophosphoric acids are first formed and, indeed, when the hydrolysis is carried out in aqueous NaOH solution at 100°, substantial amounts of the mono- and di-thiophosphates are obtained. P-S bonds are also retained during reaction of P4S10 with alcohols or phenols and the products formed are used extensively in industry for a wide variety of... 

Thio-phosphorsaure, /. thiophosphoric acid, -phtalid, n. thiophthalide. 

Thiophosphoric acid insecticides and benzodiazepines yield reddish to bluish-violet-colored chromatogram zones on a colorless background. 

The detection limits for thiophosphoric acid insecticides are 100 ng and for benzodiazepines 20 ng substance per chromatogram zone. 

It is assumed that the hydrogen bromide released on the oxidation of thiophosphoric acid insecticides with N-bromosuccinimide or bromine vapors forms intensely fluorescent salt-like derivatives with 3-hydroxyflavones — such as robinetin [1, 2, 4]. 

In freshwater systems, the only biodegradation product detected was 4-nitrophenol, which was rapidly utilized and transformed to undetectable metabolites by the microorganisms present. In seawater, the main initial product was methyl aminoparathion, formed by reduction of the nitro group (Badawy and El-Dib 1984). Studies in raw river water showed that 4-nitrophenol and dimethyl thiophosphoric acid are the main degradation products (Eichelberger and Lichtenberg 1971). 

Compound (1) phosphorylates phosphate monoesters and alcohols, although with the latter a considerable excess of alcohol is necessary to obtain satisfactory yields. In the absence of mercuric ions the milder phosphorylating species (3) can be isolated which converts monoalkyl phosphates to pyrophosphate diesters in good yield but does not react appreciably with alcohols unless catalytic amounts of boron trifluoride are added. Amine salts of (3) are converted to phosphoramidates on heating. In the presence of silver ions, O-esters of thiophosphoric acid behave as phosphorylating agents and a very mild and convenient procedure suitable for preparing labile unsymmetrical pyrophosphate diesters, such as the... 

Alkyl monoesters of thiophosphoric acid have not hitherto been readily accessible compounds owing to indifferent yields and lengthy and difficult isolation procedures. A simple preparative route involves reaction of OO-di-t-butyl hydrogen phosphorothioate with the appropriate alkyl halides followed by elimination of the t-butyl groups with dry hydrogen chloride in dichloromethane ... 

An interesting communication concerns an attempt to quantify bond orders in thiophosphoric acids using 34g and 36s-... 

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%. 

The foregoing reaction scheme had been described in a patent issued in 1934 to Clemmensen (9), who prepared certain organic esters of thiophosphoric acid embodying both aromatic and aliphatic radicals. These esters are claimed as new compositions of matter useful as fire retardants. Parathion itself is not specifically described in the patent. 

Dithiophosphoric acids, (RO)2PS2H, have been used for the thionation of carbonyl groups in certain aldehydes, ketones, amides, esters, thio-carboxylates and other organics.163 The mechanism for this reaction proceeds via a reversible nucleophilic attack of the thioacid on the carbonyl compound, which can then rearrange by way of a four-membered PSCO cyclic intermediate into the desired C=S containing molecule and thiophosphoric acid (Equation 81).163... 

The IR and Raman spectra of the thiophosphoric acid ester 14 are consistent with a polymeric structure including tetra- and pentacoordinated tin atoms128. 

Tertiary amines serve the dual role of base, to generate the Michaelis-Becker reagent from the parent dialkyl phosphorous or thiophosphorous acid, and subsequently (in the pro-tonated state) as the leaving group for displacement by the anion.179... 

Chemical/Physical. On heating, EPN is converted to the 5-ethyl isomer (Worthing and Hance, 1991). EPN is rapidly hydrolyzed in alkaline solutions to 4-nitrophenol, alcohol, and benzene thiophosphoric acid (Sittig, 1985). 

Soil. In soil, malathion was degraded by Arthrobacter sp. to malathion monoacid, masphoro-dithioate. After 10 d, degradation yields in sterile and nonsterile soils were 8, 5, and 19% and 92, 94, and 81%, respectively (Walker and Stojanovic, 1974). Chen et al. (1969) reported that the microbial conversion of malathion to malathion monoacid was a result of demethylation of the 0-methyl group. Malathion was converted by unidentified microorganisms in soil to thiomalic acid, dimethyl thiophosphoric acid, and diethylthiomaleate (Konrad et al, 1969). 

Benzene thiophosphoric acid, see EPN 1,2,4-Benzenetriol, see 2,4-D Benzidine, see Aniline, 3,3 -Dichlorobenzidine 1 -(2-Benzimidazolyl) -3-/ -butylurea, see Benomvl Benzo [ a] anthracene-7,12-dione, see Benzo [alanthracene... 

Diethyl phosphate, see Sulfotepp Diethyl phosphoric acid, see Diazinon. Parathion Diethyl phosphorothioate, see Diazinon 0,0-Diethyl phosphorothioic acid, see Chlorpyrifos, Diazinon. Malathion, Parathion Diethyl sulfide, see Chlorpyrifos Diethyl thiomalate, see Malathion Diethylthiomaleate, see Malathion Diethylthiophosphoric acid, see Diazinon. Parathion Diethyl-0-thiophosphoric acid, see Parathion... 

Dimethyl phosphorodithioic acid, see Malathion 0,0-Dimethyl phosphorophosphate, see Methoate Dimethyl phosphorothioate, see Malathion, Parathion 0,0-Dimethyl phosphorothioate, see Malathion 0,5-Dimethyl phosphorothioate, see Acephate Dimethyl phosphorothioic acid, see Dimethoate Dimethyl phosphorothionic acid, see Malathion 0,0-Dimethyl phosphorothionic acid, see Malathion Dimethyl sulfide, see Methyl mercaptan Dimethyl thiophosphate, see Malathion Dimethyl thiophosphoric acid, see Malathion Dimethyl triclopyr-aspartate, see Triclonvr Dimethyl triclopyr-glutamate, see Triclopvr... 

Tetramethylhydrazine, see Dimethylamine Tetramethylsuccinonitrile, see Aldicarb Tetrazene, see Naphthalene 2-Thiazolidinethione-4-carboxylic acid, see Captan 1.1 -Thiobis-ethane, see Phorate 3.3 -Thiobis(methylene)-1.2.3-benzotriazin-4(3Afl-one, see Azinnhos-methyl Thiomalic acid, see Malathion Thiomethylbenzazimide, see Azinphos-methyl Thiophene, see Benzene Thiophenol, see Fonofos Thiophosphoric acid, see Phorate Thiram monosulfide, see Thiram o-Tolualdehyde, see oXylene m-Tolualdehyde, see m-Xylene p-Tolualdehyde, see p-Xylene Toluene, see Benzene. 2-ChlorobiDhenyl. 4 Chlorobinhenyl. Isobutylbenzene, Methylcyclohexane, Styrene, p-Xylene... 

In this process [27], the metals are extracted successively by the same extractant, employing suitable pH values for each metal. The spent catalyst is first roasted in an air stream at 300°C to remove oil and sulfur deposited on the surface of the catalyst. Then the metals are dissolved in an ammonium carbonate leach liquor at 80°C. Finally, the three metals are isolated and purified from one another using solvent extraction with an alkylmono-thiophosphoric acid (MTPA) with a structure similar to DEHPA. The following flow sheet was suggested (Fig. 14.19) ... 

Chlorothietane was subjected to reaction with dichloro derivatives of phosphorous acid to give, after heating the reaction mixture to 150°C, the acyclic compound thiophosphoric acid in low yields. ... 

Virtually all that tested positive are methyl or ethyl esters of phosphoric or thiophosphoric acids, and are electrophilic and mutagenic (e.g., dichlorvos, tetrachlorvinphos Figure 14.12). 

Hydrolytic Reactions of Phosphoric and Thiophosphoric Acid Esters... 

---