Azoxybenzene

Azoxybenzene
Names
Preferred IUPAC name
Diphenyldiazene oxide
Other names
Azoxybenzene
1-Oxo-1,2-diphenyl-1λ5-diazene
(Diphenyldiazeniumyl)oxidanide
(Z)-1,2-Diphenyldiazene 1-oxide
[(Z)-Phenyl-NNO-azoxy]benzene
Fenazox
Identifiers
3D model (JSmol)
743984
ChEBI
ChEMBL
ChemSpider
ECHA InfoCard 100.007.094 Edit this at Wikidata
EC Number
  • 207-802-1
UNII
  • InChI=1S/C12H10N2O/c15-14(12-9-5-2-6-10-12)13-11-7-3-1-4-8-11/h1-10H
    Key: GAUZCKBSTZFWCT-UHFFFAOYSA-N
  • C1=CC=C(C=C1)N=[N+](C2=CC=CC=C2)[O-]
Properties
C12H10N2O
Molar mass 198.225 g·mol−1
Appearance yellow solid
Density 1.318 g/cm3
Melting point 35.5–36.5 °C (95.9–97.7 °F; 308.6–309.6 K)
Hazards
GHS labelling:
GHS07: Exclamation mark
Warning
H302, H332
P261, P264, P270, P271, P301+P317, P304+P340, P317, P330, P501
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Azoxybenzene is organic compound with the formula C6H5N(O)NC6H5. It is a yellow, low-melting solid. The molecule has a planar C2N2O core. The N-N and N-O bond lengths are nearly the same at 1.23 Å.

Preparation

It can be prepared by partial reduction of nitrobenzene. This reaction is proposed to proceed via the intermediacy of phenylhydroxylamine and nitrosobenzene:

PhNHOH + PhNO → PhN(O)NPh + H2O

Another option is the oxidation of aniline by hydrogen peroxide, in acetonitrile at 50 °C. In this reaction, the pH should be kept around 8, to activate the hydrogen peroxide and avoid too much oxygen evolution at the same time. First, the acetonitrile is oxidized, forming an imine hydroperoxide. Then, this intermediate oxidizes the aniline to azoxybenzene.

CH3CN + H2O2 → [CH3C(OOH)=NH]
2 PhNH2 + 3 [CH3C(OOH)=NH] → PhN(O)NPh + 3 CH3C(O)NH2 + 2 H2O
PhNO2 + Na3AsO3/NaOH→ Ph−N+O−=N-Ph

References

  1. 1 2 3 4 Nomenclature of Organic Chemistry: IUPAC Recommendations and Preferred Names 2013 (Blue Book). Cambridge: The Royal Society of Chemistry. 2014. p. 1009. doi:10.1039/9781849733069-00648. ISBN 978-0-85404-182-4.
  2. 1 2 H. E. Bigelow; Albert Palmer (1931). "Azoxybenzene". Organic Syntheses. 11: 16. doi:10.15227/orgsyn.011.0016.
  3. ↑ S. P. G. Martínez; S. Bernès (2007). "trans-Diphenyldiazene Oxide". Acta Crystallographica Section E. 63 (8): o3639. doi:10.1107/S1600536807035787.
  4. ↑ George B. Payne; Philip H. Deming; Paul H. Williams (1961). "Reactions of Hydrogen Peroxide. VII. Alkali-Catalyzed Epoxidation and Oxidation Using a Nitrile as Co-reactant". The Journal of Organic Chemistry. 26 (3): 659-663. doi:10.1021/jo01062a004.