Iron(III) azide

Iron(III) azide

Names
Other names Ferric azide Iron triazide
Identifiers
CAS Number	14215-32-8
3D model (JSmol)	Interactive image
ChemSpider	57449725
PubChem CID	57348355
CompTox Dashboard (EPA)	DTXSID00721622
InChI InChI=1S/Fe.3N3/c;3*1-3-2/q+3;3*-1 Key: MKNZTJIHKCVUHC-UHFFFAOYSA-N
SMILES [N-]=[N+]=[N-].[N-]=[N+]=[N-].[N-]=[N+]=[N-].[Fe+3]
Properties
Chemical formula	Fe(N3)3
Molar mass	181.908 g·mol−1
Appearance	Dark brown hygroscopic leaflets [1]
Melting point	200 °C (392 °F; 473 K) in air, 230 °C (446 °F; 503 K) in nitrogen [1] Explodes
Solubility in water	Soluble
Solubility in methanol	Soluble
Hazards
GHS labelling:[ citation needed ]
Pictograms
Signal word	Danger
Related compounds
Other anions	Iron(II) azide
Other cations	Arsenic(III) azide Boron triazide Chromium(III) azide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Iron(III) azide, also called ferric azide, is a chemical compound with the formula Fe(N₃)₃. It is an explosive, very unstable, hygroscopic dark brown solid. This compound is a reagent in organic chemistry. It forms red solutions in water. ^[1]

Preparation

This compound is prepared by the reaction of sodium azide and iron(III) sulfate in methanol: ^[1]

6 NaN₃ + Fe₂(SO₄)₃ → 2 Fe(N₃)₃ + 3 Na₂SO₄

Iron(III) azide can also be formed by pulse gamma-irradiation of a mixture of iron(II) perchlorate, sodium azide, and hydrogen peroxide. ^[2] Under these conditions, a neutral N₃ radical is formed, which oxidizes the iron(II) to iron(III); the iron(III) then promptly combines with azide ions.

Application in organic chemistry

In organic chemistry, ferric azide is a reagent in the one-pot conversion of alkenes to azidoalkanes, such as n-butyl azide. The process begins with a hydroboration: an anti-Markovnikov addition of an organoborane to an alkene, followed by oxidation. The nucleophilic azide anions then displace the resulting boroxy moiety from the alkane to give an azide. ^[3]

References

1. Fedoroff, Basil T.; Sheffield, Oliver E.; Clift, George D.; Reese, Earl F.; Aaronson, Henry A.; Dunkle, Cyrus G.; Walter, Hans; McLean, Dan C. (1960). "A - Azides - Iron Azide". Encyclopedia of Explosives and Related Items (PDF) (Technical report). Vol. 1, A through Azoxy. Picatinny Arsenal, NJ: U.S. Army Research and Development Command TACOM - Ardec Warheads, Energetics and Combat Support Center. p. A543. LCCN   61-61759. AD0257189, PATR2700.
2. George V. Buxton; Igor Janovský (1976). "Mechanism of the oxidation of iron(II) by the azide radical". Journal of the Chemical Society, Faraday Transactions 1: Physical Chemistry in Condensed Phases. 72: 1884–1886. doi:10.1039/F19767201884.
3. Andrew D. White (2001). "Iron(III) Azide". Encyclopedia of Reagents for Organic Synthesis. John Wiley & Sons, Ltd. doi:10.1002/047084289X.ri053. ISBN   0471936235.