Diphenylphosphoryl azide

The synthesis of 6-azidomethyl-S,6,7,8-tetrahydropterin 108 has been carried out from 106 via the intermediate 107 using the Mitsunobu reaction with diphenylphosphoryl azide followed by deprotection <95MI09 %CA(124)232123>. 

Diphenylphosphoryl azide reacts with alcohols in the presence of triphenylphosphine and DEAD.76 Hydrazoic acid, HN3, can also serve as the azide ion source under these conditions.77 These reactions are examples of the Mitsunobu reaction. 

Diphenylphosphoryl azide also gives good conversion of primary alkyl and secondary benzylic alcohols to azides in the presence of the strong organic base diazabicyc-loundecane (DBU). These reactions proceed by O-phosphorylation followed by Sw2 displacement.78... 

The transformation can also be carried out on the acid using diphenylphosphoryl azide (DPPA).266... 

Two other results will now be pointed out which presumably also require reinterpretation in the light of the reaction behavior of iminooxophosphoranes. Thus the gas phase pyrolysis of diphenylphosphoryl azide is reported to give monomeric 92 50) and the dehydrohalogenation of phenylphosphoric adamantylamidic chloride with methylhydrazine the heterocumulene 93 51), which is even considered resistant to water. Since partly correct analytical values are available, 92 and 93 may well be oligomers. 

T Shiori, T Ninomia, S Yamada. Diphenylphosphoryl azide. A new convenient reagent for a modified Curtius reaction and for peptide synthesis. J Am Chem Soc 94, 6203,... 

Diphenylphosphoryl azide was 98% as purchased from Aldrich Chemical Company, Inc., and the water content was less than 0.01 mg/mL by Karl Fisher titration. 

Diphenylphosphoryl azide Phosphorazidic acid, diphenyl ester (8, 9) ... 

Carboxylic acids can also be activated by formation of mixed anhydrides with various phosphoric acid derivatives. Diphenylphosphoryl azide, for example, is an effective... 

Azides [e.g. (+)-neomenthyl azide no physical data reported] are formed efficiently by inversion, from the corresponding alcohols and diphenylphosphoryl azide, in the presence of triphenylphosphine and diethyl azodicarboxylate [which has also been used for esterification with inversion (Vol. 5, p. 334) for a related esterification of (—)-menthol see ref. 119] a conceptually similar synthesis also yields (+)-neomenthyl azide. Cyanoselenenylation of aldehydes and of alcohols has been reported thus treatment of geraniol with o-nitrophenyl seleno-cyanide-Bu sP-THF yields the selenide (19) which can be converted into the... 

Dihydro-2-quinazolinones are available from diphenylamine-2-acetic acids via isocyanate intermediates, and thus the nonsteroidal anti-inflammatory agent diclofenac 745 gave the dihydro derivative 746 in 63% yield on treatment with diphenylphosphoryl azide <2004BML357>. 

Cyclobutanecarboxylic acid azides react in a similar manner. The azides were either made from the acid chloride and sodium azide44,45 or directly from the acid by reaction with diphenylphos-phoryl azide.37,46,47 The carboxylic acid azides rearrange via the isocyanates. An example is the reaction of (+ )-ra-2-acetoxycyclobutanecarboxylic acid with diphenylphosphoryl azide to give 4 in quantitative yield.37... 

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