Pyrophosphate

"Diphosphate" redirects here. It can also refer to any salt containing two phosphate groups.
Pyrophosphate
Pyrophosphate anion
  Phosphorus, P
  Oxygen, O
Names
IUPAC name
Diphosphate
Systematic IUPAC name
Dipolyphosphate
Other names
Pyrophosphate
Phosphonatophosphate
Identifiers
3D model (JSmol)
ChEBI
ChemSpider
DrugBank
E number E450 (thickeners, ...)
26938
UNII
  • InChI=1S/H4O7P2/c1-8(2,3)7-9(4,5)6/h(H2,1,2,3)(H2,4,5,6)/p-4 checkY
    Key: XPPKVPWEQAFLFU-UHFFFAOYSA-J checkY
  • InChI=1/H4O7P2/c1-8(2,3)7-9(4,5)6/h(H2,1,2,3)(H2,4,5,6)/p-4
    Key: XPPKVPWEQAFLFU-XBHQNQODAI
  • [O-]P(=O)([O-])OP(=O)([O-])[O-]
Properties
P2O4−7
Molar mass 173.941 g·mol−1
Conjugate acid Pyrophosphoric acid
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
checkY verify (what is checkY☒N ?)

In chemistry, pyrophosphates are phosphorus oxyanions that contain two phosphorus atoms in a P−O−P linkage. A number of pyrophosphate salts exist, such as disodium pyrophosphate (Na2H2P2O7) and tetrasodium pyrophosphate (Na4P2O7), among others. Often pyrophosphates are called diphosphates. The parent pyrophosphates are derived from partial or complete neutralization of pyrophosphoric acid. The pyrophosphate bond is also sometimes referred to as a phosphoanhydride bond, a naming convention which emphasizes the loss of water that occurs when two phosphates form a new P−O−P bond, and which mirrors the nomenclature for anhydrides of carboxylic acids. Pyrophosphates are found in ATP and other nucleotide triphosphates, which are important in biochemistry. The term pyrophosphate is also the name of esters formed by the condensation of a phosphorylated biological compound with inorganic phosphate, as for dimethylallyl pyrophosphate. This bond is also referred to as a high-energy phosphate bond.