Iodine azide

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Structural formula
Structure of iodine azide
General
Surname Iodine azide
Molecular formula IN 3
Brief description

colorless, highly explosive solid

External identifiers / databases
CAS number 14696-82-3
PubChem 61763
ChemSpider 55652
Wikidata Q1624428
properties
Molar mass 168.92 g mol −1
Physical state

firmly

Vapor pressure

2 Torr (25 ° C)

solubility

Decomposes in water

safety instructions
GHS hazard labeling
no classification available
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Iodine azide , IN 3 , is a colorless to yellow, extremely explosive, solid chemical compound from the group of nitrogen halides . Formally it belongs to the inter- pseudohalogens . Iodine azide should not be confused with the also explosive iodine nitrogen , NI 3 .

Extraction and presentation

Iodine azide can be obtained by reacting silver azide AgN 3 with iodine in a CFCl 3 solution.

Of water can Since silver azide just damp handle safely, traces are already the decomposition of iodine azide cause succeeds its preparation best if before the reaction with iodine to the suspension of the Silberazids in dichloromethane , a drying agent is added. In this way, a pure solution of iodine azide is obtained, from which needle-shaped, gold-shining crystals can be isolated if the solvent is carefully evaporated.

Iodine azide was obtained for the first time around 1900 in very volatile ethereal solutions and in the form of crystals contaminated with iodine by the reaction of iodine with silver azide.

properties

Iodine azide is in the form of a one-dimensional polymer. Two polymorphic forms are formed, both of which form an orthorhombic crystal lattice with the space group Pbam (space group no. 55) . The high reactivity of iodine azide with relatively high stability is due to the polarity of the I – N bond. The N 3 group introduced by substitution with iodine azide can enter into secondary reactions because of its high energy content. Template: room group / 55

The isolated connection is very sensitive to impact and friction . The following parameters were determined to characterize the explosiveness:

Normal gas volume 265 l kg −1
Explosion heat 2091 kJ kg −1
Lead block bulge 14.0 cm 3 g −1

These are significantly lower compared to classic explosives such as TNT or hexogen, but also to acetone peroxide . Handling the compound in dilute solution is considered safe.

use

Despite its high explosiveness, iodine azide has some practical applications, for example it can be used in chemical synthesis to convert aldehydes into carboxylic acid azides .

literature

Web links

Individual evidence

  1. Entry on iodine azide. In: Römpp Online . Georg Thieme Verlag, accessed on July 15, 2014.
  2. a b c d e Buzek, P .; Klapötke, TM ; By Ragué Schleyer, P .; Tornieporth-Oetting, IC; White, PS: iodine azide in Angew. Chem. 105 (1993) 289-290, doi: 10.1002 / anie. 19931050228
  3. a b c Kurt Dehnicke : Die Chemie des Iodazids , Angewandte Chemie , 91 (7), 1979, 527-534, doi: 10.1002 / anie.19790910704 .
  4. This substance has either not yet been classified with regard to its hazardousness or a reliable and citable source has not yet been found.
  5. a b A. Hantzsch, M. Schumann: Reports of the German Chemical Society , 33, 522, 1900.
  6. a b Lyhs, B .; Bläser, D .; Wölper, C .; Schulz, S .; Jansen, G .: Solid-state structure comparison of the halogen azides XN 3 (X = Cl, Br, I) in Angew. Chem. 124 (2012) 13031-13035, doi: 10.1002 / anie.201206028 .
  7. Urben, PG: Bretherick's Handbook of Reactive Chemical Hazards , 6th Ed., Vol. 1, Butterworth-Heinemann 1999, ISBN 0-7506-3605-X , p. 1713.
  8. Dehnicke, K., Angew. Chem. (Intern. Ed.), 1976, 15, 553.
  9. L. Marinescu, J. Thinggaard, B. Thomsen, M. Bols, J. Org. Chem. , (2003) 68, 9453-9455