Org. Synth. 1984, 62, 187
[Phosphorazidic acid, diphenyl ester]
Submitted by Takayuki Shioiri1
and Shun-ichi Yamada2
Checked by Christina Bodurow and M. F. Semmelhack.
A mixture of 56.8 g (0.21 mol) of diphenyl phosphorochloridate (Note 1), 16.3 g (0.25 mol) of sodium azide, and 300 mL of anhydrous acetone (Note 2) in a 500-mL round-bottomed flask fitted with a calcium chloride tube is stirred at 20–25°C for 21 hr. The lachrymatory mixture is filtered in a hood, and the filtrate is concentrated under reduced pressure. The residue is distilled through a short Vigreux column (Note 3). The yield of diphenyl phosphorazidate, bp 134–136°C (0.2 mm), is 49–52 g (84–89%) (Note 4).
Diphenyl phosphorochloridate (diphenyl chlorophosphate), from Aldrich Chemical Company, Inc.
, was used after purification by distillation at 165–168°C (5 mm).
was dried over anhydrous potassium carbonate
The bath temperature should be kept below 200°C to minimize decomposition of diphenyl phosphorazidate
is a colorless nonexplosive oil that can be kept for a long time without decomposition if it is protected against light3
The procedure described is essentially that of Shioiri and Yamada.4 Diphenyl phosphorazidate
is a useful and versatile reagent in organic synthesis.5 6
It has been used for racemization-free peptide syntheses,4,7,8
thiol ester synthesis,9
a modified Curtius reaction,7,10,11 C
-acylation of active methylene compounds,12
esterification of an α-substituted carboxylic acid,13
formation of diketopiperazines,14
an alkyl azide synthesis,15
phosphorylation of alcohols and amines,16
and polymerization of amino acids and peptides.17
Furthermore, diphenyl phosphorazidate
acts as a nitrene source3
and as a 1,3-dipole.18,19
An example of the ring contraction of cyclic ketones to form cycloalkanecarboxylic acids is presented on page 135 in this volume.
This preparation is referenced from:
Chemical Abstracts Nomenclature (Collective Index Number);
Diphenyl phosphorochloridate (diphenyl chlorophosphate)
potassium carbonate (584-08-7)
sodium azide (26628-22-8)
diphenyl phosphorochloridate (2524-64-3)
Phosphorazidic acid, diphenyl ester (26386-88-9)
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