Thiophosphate

Thiophosphate
For the thiophosphate esters see organothiophosphates.

A thiophosphate (or phosphorothioate) is a family of compounds and anions with the general chemical formula PS4-xOx3- (x = 0, 1, 2, or 3). The state of protonation is usually not specified. They could be bound to as many as three protons for the neutral H3PS4-xOx species. Two protons correspond to the related monoanions, and one proton for the dianions. The trianions are highly basic and do not exist in appreciable concentrations in solution. Thiophosphates are tetrahedral anions, with the phosphorus at the center of the tetrahedron.

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Monothiophosphate

Ball-and-stick model of the monothiophosphate ion

Monothiophosphates are formally derived from the anion PO3S3-, which has C3v symmetry.. A number of insecticides feature organic monothiophosphate center, including diazinon, parathion, and malathion. They have the formula (RO)2PS(OAr), where R = methyl or ethyl and Ar = an aryl or related group. Coordination complexes of are known.[1]

In the laboratory monothiophosphate is used as an analogue of phosphate in biochemistry. Monothiophosphate esters are biochemical reagents used in the study transcription,[2] substitution interference assays.

Dithiophosphates

Dithiophosphates are formally derived from the anion PO2S23-, which has C2v symmetry. This species is the major product from the reaction of base (e.g., NaOH) with phosphorus pentasulfide. The sodium salt has the nominal formula Na3PO2S2, but is invariably hydrated. The main application of this dithiophosphate salt is in the purification of molybdenite ore. Organic thiophosphates feature the (RO)2PS2- anion (R = alkyl, aryl). Zinc dithiophosphate, e.g., Zn(S2P(OR)2)2]], are used as oil additives (R = alkyl).

Tri- and tetrathiophosphates

Trithiophosphates are formally derived from the anion POS33-, which has C3v symmetry. Tetrathiophosphate has the formula PS43-. Derivatives of these two anions are less commonly encountered.

References


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Look at other dictionaries:

  • thiophosphate — [thī΄ō fäs′fāt΄] n. a salt or ester of a thiophosphoric acid …   English World dictionary

  • thiophosphate — /thuy oh fos fayt/, n. Chem. a salt or ester of thiophosphoric acid. [THIO + PHOSPHATE] * * * …   Universalium

  • thiophosphate — noun Any compound formally derived from a phosphate by replacing one or more oxygen atoms with sulfur Syn: phosphorthioate, phosphorothioate …   Wiktionary

  • thiophosphate — thio·phos·phate .thī ō fäs .fāt n a salt or ester of an acid derived from a phosphoric acid by replacement of one or more atoms of oxygen with sulfur …   Medical dictionary

  • thiophosphate — thio·phosphate …   English syllables

  • thiophosphate — “+ noun Etymology: International Scientific Vocabulary thi + phosphate : a salt or ester of a thiophosphoric acid * * * /thuy oh fos fayt/, n. Chem. a salt or ester of thiophosphoric acid. [THIO + PHOSPHATE] …   Useful english dictionary

  • Dithiophosphorsäureester — Strukturformel Allgemeines Name Thiophosphorsäure Andere Namen Monothiophosphorsäure …   Deutsch Wikipedia

  • Phosphorothioat — Strukturformel Allgemeines Name Thiophosphorsäure Andere Namen Monothiophosphorsäure …   Deutsch Wikipedia

  • Thiophosphat — Strukturformel Allgemeines Name Thiophosphorsäure Andere Namen Monothiophosphorsäure …   Deutsch Wikipedia

  • Thiophosphorsäure — Strukturformel Allgemeines Name Thiophosphorsäure Andere Namen …   Deutsch Wikipedia

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