Diphenylphosphoryl azide
| Diphenylphosphoryl azide | |
|---|---|
| File:Diphenylphosphoryl azide.png | |
| File:DPPA-3D-balls.png | |
| Other names Diphenylphosphonic azide Diphenyl azidophosphate Phosphoric acid diphenyl ester azide | |
| style="background: #F8EABA; text-align: center;" colspan="2" | Identifiers | |
| CAS number | 26386-88-9 
|
| PubChem | 123414 |
| SMILES | Script error: No such module "collapsible list". |
| style="background: #F8EABA; text-align: center;" colspan="2" | Properties | |
| Molecular formula | C12H10N3O3P |
| Molar mass | 275.20 g/mol |
| Appearance | Colourless or faintly yellow liquid |
| Density | 1.277 g/cm3 |
| Boiling point |
157 °C (0.2 mmHg) |
| style="background: #F8EABA; text-align: center;" colspan="2" | Hazards | |
| EU classification | Toxic (C) |
 (what is this?) (verify)Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) | |
| Infobox references | |
Diphenylphosphoryl azide (DPPA) is an organic compound. It is widely used in synthesis of other organic compounds.[1] Diphenylphosphoryl azide has been obtained by reaction of the phosphorochloridate with sodium azide. The stability of the azide towards heating was shown by its distillation at 157 °C and by the fact that vigorous evolution of nitrogen was not observed until a temperature of 175 °C had been reached.
Uses
This compound undergoes pseudohalogen replacement of the azido group by treatment with nucleophilic reagents, such as water, butanol, ammonia, and various amines.
This compound is used as a reagent for the synthesis of peptides by virtue of its reactions with carboxylic acids leading to either the urethane or the amide. The formation of the urethane is particularly valuable since it works with carboxylic acids which fail to undergo the Schmidt reaction, and is believed to involve transfer of the azido group to the carboxylic acid.
It is now suggested that this reaction proceeds through the intermediate mixed anhydride, resulting from attack by the nucleophilic carboxylate anion on the phosphorus atom, with expulsion of the azide ion. The latter then attacks the carbonyl carbon atom, to give the acyl azide and loss of the diphenyl phosphate anion, known to be a good leaving group. Finally, the acyl azide reacts in the normal manner to give the urethane.
The present studies show that diphenylphosphoryl azide reacts with amines giving the corresponding phosphoramidates; it therefore appears that formation of the amide similarly involves the intermediate anhydride, followed by nucleophilic substitution by the amine.
References
Cite error: Invalid <references> tag;
parameter "group" is allowed only.
<references />, or <references group="..." />- ↑ Some Reactions of O,O-Diphenylphosporyl Azide, Aust. J. Chem., 1973, 26, 1591-3.
