Diamidophosphate

Diamidophosphate is the simplest phosphorodiamidate ion, with formula PO₂₂⁻. It is a phosphorylating ion and was first used for the phosphorylation of sugars in aqueous medium. DAP has attracted interest in the area of primordial chemistry.

Salts

Several salts of the formula MPO₂₂_x are known.

The sodium salt can be made by base hydrolysis of phenyl phosphorodiamidate. It crystallises as a hexahydrate. It can be dehydrated.
The silver salt AgPO₂₂ can react using double decomposition with bromides forming other salts.
The potassium dithiophosphate salt KPO₂₂ is also known.
Phosphorodiamidic acid crystallizes as a trihydrate.

Reactions

Heating anhydrous sodium diamidophosphate causes polymerization:

At 160 °C, Na₂P₂O₄₂, Na₃P₃O₆₂₂, Na₄P₄O₈₃₂, Na₅P₅O₁₀₄₂ and Na₆P₆O₁₂₅₂ are produced. These substances contain P-N-P backbones. These can be separated by paper chromatography.
At 200 °C the hexa-phosphate is produced.
At 250 °C the typical chain length is 18.

Heating hydrated salts induces the loss of ammonia to form oligophosphates and polyphosphates.
Diamidophosphate inhibits urease enzymes by blocking up the active site, binding to two nickel centers. Diamidophosphate mimics the urea hydrolysis intermediate.
Diamidophosphate is tribasic, and the amine groups may also lose hydrogen to form more metallic salts. With silver, further reactions can yield explosive salts: tetrasilver orthodiamidophosphate ₃PNHAg, and pentasilver orthodiamidophosphate ₃P₂.

Organic esters and amides

image:PhOPO2.svg|thumb|left|Phenyl phosphorodiamidate, an inhibitor of urease, is a controlled release fertilizer.
Numerous organic derivatives are known. One example is phenyl phosphorodiamidate.

Reactions with nucleosides

DAP phosphorylates deoxynucleosides from smaller RNA strands. Other nitrogenous derivatives of phosphorus derivatives have also been proposed in this context in a review article.