Acyl azide

General chemical structure of an acyl azide

Acyl azides are carboxylic acid derivatives with the general formula RCON3. These compounds, which are a subclass of organic azides, are generally colorless.

Preparation

Diphenylphosphoryl azide

Typically acyl azides are generated under conditions where they rearrange to the isocyanate.

Acid chlorides and anhydrides react with sodium azide or trimethylsilyl azide to give acyl azides:

In a Mitsunobu variant, triphenylphosphine and trichloroacetonitrile catalyze excellent yields from various carboxylic acids and sodium azide at mild conditions.

The second major route to azides is from treating acylhydrazines with nitrous acid. Alternatively, the acyl azide can be formed by the direct reaction of a carboxylic acid with diphenylphosphoryl azide (DPPA).

Methods of forming acyl azides from carboxylic acids
Methods of forming acyl azides from carboxylic acids

Another route oxidizes aldehydes with iodine azide, formed from sodium azide and iodine monochloride in acetonitrile.

Uses

On Curtius rearrangement, acyl azides yield isocyanates.

Acyl azides are also formed in Darapsky degradation,

Darapsky degradation

Acyl azides react with amines to give aminimides (R3N+N−C(=O)R′).

Historical references

References

  1. 1 2 3 Lwowski, Walter (1971). "Acyl azides". In Saul Patai (ed.). The Azido Group. PATAI'S Chemistry of Functional Groups. pp. 849–907. doi:10.1002/9780470771266.ch9. ISBN 9780470771679.
  2. ↑ Allen, C. F. H.; Bell, Alan (1944). "Undecyl isocyanate". Organic Syntheses. 24: 94. doi:10.15227/orgsyn.024.0094.
  3. ↑ Munch-Petersen, Jon (1953). "m-Nitrobenzazide (Benzoyl azide, m-nitro-)". Organic Syntheses. 33: 53. doi:10.15227/orgsyn.033.0053.
  4. ↑ Weinstock, J (1961). "Modified Curtius reaction". J. Org. Chem. 26: 3511. doi:10.1021/jo01067a604.
  5. ↑ Carey, Francis A.; Sundberg, Richard J. (2007). Advanced Organic Chemistry: Part B: Reactions and Synthesis (5th ed.). New York: Springer. p. 948. ISBN 978-0387683546.
  6. ↑ Warren, J. D.; Press, J. B. (1980). "Formation and Curtius rearrangement of acyl azides from unreactive acid chlorides". Synth. Commun. 10: 107–110. doi:10.1080/00397918008061812.
  7. ↑ Jang, Doo; Kim, Joong-Gon (2008). "Direct Synthesis of Acyl Azides from Carboxylic Acids by the Combination of Trichloroacetonitrile, Triphenylphosphine and Sodium Azide". Synlett. 2008 (13): 2072–2074. doi:10.1055/s-2008-1077979.
  8. ↑ Pozsgay, V.; Jennings, H. J. (1987). "Azide synthesis with stable nitrosyl salts". Tetrahedron Lett. 28 (43): 5091–5092. doi:10.1016/s0040-4039(00)95598-9.
  9. ↑ Shioiri, T.; Ninomiya, K.; Yamada, S. (1972). "New convenient reagent for a modified Curtius reaction and for peptide synthesis". J. Am. Chem. Soc. 94 (17): 6203–6205. doi:10.1021/ja00772a052. PMID 5054412.
  10. ↑ Carey, Francis A.; Sundberg, Richard J. (2007). Advanced Organic Chemistry: Part B: Reactions and Synthesis (5th ed.). New York: Springer. p. 948. ISBN 978-0387683546.
  11. ↑ Marinescu, Lavinia; Thinggaard, Jacob; Thomsen, Ib B.; Bols, Mikael (2003). "Radical Azidonation of Aldehydes". J. Org. Chem. 68 (24): 9453–9455. doi:10.1021/jo035163v. PMID 14629171.
  12. ↑ Smith, Peter A. S. (1946). "The Curtius reaction". Org. React. 3: 337–449. doi:10.1002/0471264180.or003.09. ISBN 0471264180. {{cite journal}}: ISBN / Date incompatibility (help)CS1 maint: periodical has ISBN (link)
  13. ↑ Scriven, Eric F. V.; Turnbull, Kenneth (1988). "Azides: Their preparation and synthetic uses". Chem. Rev. 88 (2): 297–368. doi:10.1021/cr00084a001.
  14. ↑ Gagnon, Paul E.; Boivin, Paul A.; Craig, Hugh M. (1951). "Synthesis of Amino Acids from Substituted Cyanoacetic Esters". Can. J. Chem. 29 (1): 70–75. doi:10.1139/v51-009.
  15. ↑ E. H. Rodd (1965). Chemistry of Carbon Compounds (2nd ed.). New York. p. 1157.{{cite book}}: CS1 maint: location missing publisher (link)
  16. ↑ Gagnon, Paul E.; Nadeau, Guy; Côté, Raymond (1952). "Synthesis of α-Amino Acids from Ethyl Cyanoacetate". Can. J. Chem. 30 (8): 592–597. doi:10.1139/v52-071.
  17. ↑ Wawzonek, Stanley (1980). "Chemistry of Aminimides". Industrial & Engineering Chemistry Product Research and Development. 19 (3): 338–349. doi:10.1021/i360075a013. ISSN 0196-4321.