Monofluorophosphate is an anion with the formula , which is a phosphate group with one oxygen atom substituted with a fluoride atom. The charge of the ion is −2. The ion resembles sulfate in size, shape and charge, and can thus form compounds with the same structure as sulfates. These include Tutton's salts and langbeinites. The most well-known compound of monofluorophosphate is

sodium monofluorophosphate Sodium monofluorophosphate, commonly abbreviated SMFP, is an inorganic compound with the chemical formula Na2PO3F. Typical for a salt, SMFP is odourless, colourless, and water-soluble. This salt is an ingredient in some toothpastes.Klaus Schrödte ...

, commonly used in toothpaste. Related ions include difluorophosphate () and

hexafluorophosphate Hexafluorophosphate is an fluoroanion, anion with chemical formula of . It is an Octahedral molecular geometry, octahedral species that imparts no color to its salts. is isoelectronic with sulfur hexafluoride, , and the Hexafluorosilicic acid, h ...

(). The related neutral molecule is phosphenic fluoride . Organic derivatives can be highly toxic and include

diisopropyl fluorophosphate Diisopropyl fluorophosphate (DFP) or Isoflurophate is an oily, colorless liquid with the chemical formula C6H14FO3P. It is used in medicine and as an organophosphorus insecticide. It is stable, but undergoes hydrolysis when subjected to moisture ...

. Some of the Novichok agents are monofluorophosphate esters. Names are given to these by naming the groups attached as esters and then adding "fluorophosphonate" to the end of the name. Two organic groups can be attached. Other related nerve gas substances may not be esters, and instead have carbon-phosphorus or nitrogen-phosphorus bonds. The organic fluorophosphonates react with serine esterases and

serine protease Serine proteases (or serine endopeptidases) are enzymes that cleave peptide bonds in proteins. Serine serves as the nucleophilic amino acid at the (enzyme's) active site. They are found ubiquitously in both eukaryotes and prokaryotes. Serin ...

s irreversibly. This prevents these enzymes from functioning. Such an important enzyme is

acetylcholinesterase Acetylcholinesterase (HUGO Gene Nomenclature Committee, HGNC symbol ACHE; EC 3.1.1.7; systematic name acetylcholine acetylhydrolase), also known as AChE, AChase or acetylhydrolase, is the primary cholinesterase in the body. It is an enzyme th ...

as found in most animals. Some of the organic esters are detoxified in mammals by an enzyme in the blood and liver called

paraoxonase Paraoxonases are a protein family, family of mammalian enzymes with aryldialkylphosphatase activity. There are three paraoxonase isozymes, which were originally discovered for their involvement in the hydrolysis of organophosphates. Research ...

PON1 Paraoxonase 1 (PON1) also known as Serum paraoxonase and arylesterase 1, A esterase, homocysteine thiolactonase or serum aryldialkylphosphatase 1, is an enzyme that in humans is encoded by the ''PON1'' gene. Paraoxonase 1 has esterase and more sp ...

. Willy Lange from Berlin discovered sodium monofluorophosphate in 1929. He fruitlessly tried to make monofluorophosphoric acid. However, he did discover the highly toxic organic esters. Following this discovery various nerve gases like

sarin Sarin (NATO designation GB nerve_agent#G-series.html" ;"title="hort for nerve agent#G-series">G-series, "B" is an extremely toxic organophosphorus compound.SnO Sno or SNO may refer to: People * Evander Sno (born 1987), Dutch football coach and former player * Shaquill Sno (born 1996), Dutch footballer Other uses * " Snö", a song by Iranian-Swedish singer-songwriter Laleh * Sakon Nakhon Airport, T ...

, 40% , 50% forms a glass melting about 139 °C. PbO and can lower the melting temperature, and increase water resistance. These glasses can also be coloured by various other elements, and organic dyes. Some

mixed anion compounds Mixed-anion compounds, heteroanionic materials or mixed-anion materials are chemical compounds containing cations and more than one kind of anion. The compounds contain a single phase, rather than just a mixture. Use in materials science By having ...

are known with other anions like

fluoride Fluoride (). According to this source, is a possible pronunciation in British English. is an Inorganic chemistry, inorganic, Monatomic ion, monatomic Ion#Anions and cations, anion of fluorine, with the chemical formula (also written ), whose ...

, chloride, difluorophosphate or tetrafluoroborate.

Production

Hydrolysis of difluorophosphate with an alkali produces monofluorophosphate. : Industrial production is by reaction of a

with a

metaphosphate A metaphosphate ion is an oxyanion that has the empirical formula . It was first postulated in 1955 but was not observed until 1979, when it was detected by mass spectrometry. Metaphosphate is an intermediate in the hydrolysis of phosphate esters ...

. :

Disodium hydrogen phosphate Disodium phosphate (DSP), or disodium hydrogen phosphate, or sodium phosphate dibasic, is an inorganic compound with the chemical formula . It is one of several sodium phosphates. The salt is known in anhydrous form as well as hydrates , where ' ...

or tetrasodium pyrophosphate can react with hydrogen fluoride to form the sodium salt. : or Phosphoric acid reacts with metal fluorides dissolved in molten

urea Urea, also called carbamide (because it is a diamide of carbonic acid), is an organic compound with chemical formula . This amide has two Amine, amino groups (–) joined by a carbonyl functional group (–C(=O)–). It is thus the simplest am ...

to yield monofluorophosphates.

Properties

Monofluorophosphates are stable at room temperature, but will decompose when heated. For example, at , silver monofluorophosphate gives off phosphoryl fluoride () as a gas leaving behind silver phosphate () and silver pyrophosphate (). In inorganic compounds the monofluorophosphate ion has an average P–O bond length of 1.51 Å. The P–F bond is longer, on average 1.58 Å. The O P F angle is 104.8°, smaller than the tetrahedral 109.47°. To compensate the O P O bond angle is 113.7° on average. Most commonly the monofluorophosphtae ion takes on point group 1, but a significant number have point group ''m''. Only two are known with 3''m'' and one with 3. When compared to sulfates, some are isotypical with the monofluorophosphates. Yet others have sulfates that take on a different form. But most know monofluorophosphates have no known equivalent sulfate.

Compounds

Organic

Uses

Zinc monofluorophosphate can be used as a corrosion inhibitor for steel when salt is present. Glutamine monofluorophosphate has been used as a fluoride-bearing medicine.

Production

Properties

Compounds

Organic

Uses

References

Other reading