Acyl azide

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General chemical structure of an acyl azide Acyl azide.svg
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. [1]

Contents

Preparation

Typically acyl azides are generated under conditions where they rearrange to the isocyanate. [1]

Alkyl or aryl acyl chlorides react with sodium azide to give acyl azides. [2] [3]

Preparation of acyl azides from acyl chlorides.png

The second major route to azides is from the acyl hydrazides with nitrous acid. [1]

Acyl azides have also been synthesized from various carboxylic acids and sodium azide in presence of triphenylphosphine and trichloroacetonitrile catalysts in excellent yields at mild conditions. [4] Another route starts with aliphatic and aromatic aldehydes reacting with iodine azide which is formed from sodium azide and iodine monochloride in acetonitrile. [5]

Uses

On Curtius rearrangement, acyl azides yield isocyanates. [6] [7]

Curtius Rearrangement Scheme.png

Acyl azides are also formed in Darapsky degradation, [8] [9] [10]

Degradacion de Darapsky.png

Historical references

Related Research Articles

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In organic chemistry, an acyl chloride is an organic compound with the functional group −C(=O)Cl. Their formula is usually written R−COCl, where R is a side chain. They are reactive derivatives of carboxylic acids. A specific example of an acyl chloride is acetyl chloride, CH3COCl. Acyl chlorides are the most important subset of acyl halides.

<span class="mw-page-title-main">Acyl halide</span> Oxoacid compound with an –OH group replaced by a halogen

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<span class="mw-page-title-main">Curtius rearrangement</span> Chemical reaction

The Curtius rearrangement, first defined by Theodor Curtius in 1885, is the thermal decomposition of an acyl azide to an isocyanate with loss of nitrogen gas. The isocyanate then undergoes attack by a variety of nucleophiles such as water, alcohols and amines, to yield a primary amine, carbamate or urea derivative respectively. Several reviews have been published.

<span class="mw-page-title-main">Favorskii rearrangement</span> Chemical reaction

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α-Halo ketone

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<span class="mw-page-title-main">Aceturic acid</span> Chemical compound

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An organic azide is an organic compound that contains an azide functional group. Because of the hazards associated with their use, few azides are used commercially although they exhibit interesting reactivity for researchers. Low molecular weight azides are considered especially hazardous and are avoided. In the research laboratory, azides are precursors to amines. They are also popular for their participation in the "click reaction" between an azide and an alkyne and in Staudinger ligation. These two reactions are generally quite reliable, lending themselves to combinatorial chemistry.

Lauroyl chloride is the organic compound with the formula CH3(CH2)10COCl. It is the acid chloride of lauric acid. Lauroyl chloride is a standard reagent for installing the lauroyl group. It is mainly produced as a precursor to dilauroyl peroxide, which is widely used in free-radical polymerizations.

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. 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.
  5. 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.
  6. Smith, Peter A. S. (1946). "The Curtius reaction". Org. React. 3: 337–449. doi:10.1002/0471264180.or003.09. ISBN   0471264180.
  7. Scriven, Eric F. V.; Turnbull, Kenneth (1988). "Azides: Their preparation and synthetic uses". Chem. Rev. 88 (2): 297–368. doi:10.1021/cr00084a001.
  8. 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 .
  9. E. H. Rodd (1965). Chemistry of Carbon Compounds (2nd ed.). New York. p. 1157.{{cite book}}: CS1 maint: location missing publisher (link)
  10. 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 .