Nitrogen tribromide
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| IUPAC name
nitrogen tribromide
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3D model (JSmol)
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PubChem CID
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CompTox Dashboard (EPA)
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| Properties | |||
| NBr3 | |||
| Molar mass | 253.7187 g/mol | ||
| Appearance | Deep red solid | ||
| Melting point | Explodes at -100 °C[1] | ||
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Nitrogen tribromide is a chemical compound with the formula NBr3. It is extremely explosive in its pure form, even at −100 °C, and was not isolated until 1975.[2] It is a deep-red and volatile solid.
Preparation
[edit]NBr3 was first prepared by reaction of bistrimethylsilylbromamine (bis(trimethylsilyl)amine bromide) with bromine monochloride (with trimethylsilyl chloride as byproduct) at −87 °C according to the following equation:
- (Me3Si)2NBr + 2 BrCl → NBr3 + 2 Me
3SiCl
where "Me" is a methyl group.
NBr3 can be produced by the reaction of bromine or hypobromite and ammonia in a dilute aqueous buffer solution.[3] It can also be prepared by the reaction of bromine and bromine azide.[4] Ammonia and bromine undergo glow discharge, and after treatment, red NBr3·6NH3 can be obtained.[5] Pure nitrogen NBr3 was only produced in 1975.[6]
Reactions
[edit]Nitrogen tribromide reacts instantly with ammonia in dichloromethane solution at −87 °C to yield NBrH2.[7]
- NBr3 + 2 NH3 → 3 NH2Br
It also reacts with iodine in dichloromethane solution at −87 °C to produce NBr2I, which is a red-brown solid that stable up to -20 °C.[7]
- NBr3 + I2 → NBr2I + IBr
References
[edit]- ^ Lide, David R. (1998), Handbook of Chemistry and Physics (87 ed.), Boca Raton, Florida: CRC Press, pp. 4–73, ISBN 0-8493-0594-2
- ^ Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. p. 439. ISBN 978-0-08-037941-8.
- ^ Galal-Gorchev, Hend; Morris, J. Carrell (Jun 1965). "Formation and Stability of Bromamide, Bromimide, and Nitrogen Tribromide in Aqueous Solution". Inorganic Chemistry. 4 (6): 899–905. doi:10.1021/ic50028a029. ISSN 0020-1669.
- ^ Klapötke, Thomas M. (1997-01-01). "The reaction of bromine azide with bromine". Polyhedron. 16 (15): 2701–2704. doi:10.1016/S0277-5387(96)00586-4. ISSN 0277-5387.
- ^ Schmeisser, Martin (1941-05-07). "Über Bromstickstoff". Zeitschrift für anorganische und allgemeine Chemie. 246 (3): 284–302. doi:10.1002/zaac.19412460305. ISSN 0863-1786.
- ^ Jander, Jochen; Knackmuss, Jürgen; Thiedemann, Klaus-Ulrich (1975-06-01). "Notizen: Darstellung und Isolierung von Stickstofftribromid NBr3 und Stickstoffdibromidmonojodid NBr2J / Preparation and Isolation of Nitrogentribromide NBr3 and Nitrogendibromidemonoiodide NBr2I". Zeitschrift für Naturforschung B. 30 (5–6): 464–465. doi:10.1515/znb-1975-5-633. ISSN 1865-7117.
- ^ a b Matyáš, Robert; Pachman, Jiří. (2013). Primary explosives. Berlin: Springer. p. 294. ISBN 978-3-642-28436-6. OCLC 832350093.