Sodium hypobromite
IUPAC name
Sodium hypobromite
3D model (JSmol)
ECHA InfoCard 100.034.096 Edit this at Wikidata
EC Number
  • 237-520-4
  • InChI=1S/BrO.Na/c1-2;/q-1;+1
  • [O-]Br.[Na+]
Molar mass 118.893 g·mol−1
Appearance orange solid
Related compounds
Other anions
Related compounds
Hypobromous acid
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Sodium hypobromite is an inorganic compound with the chemical formula NaOBr. It is a sodium salt of hypobromous acid. It consists of sodium cations Na+ and hypobromite anions OBr. It is usually obtained as the pentahydrate, so the compound that is usually called sodium hypobromite actually has the formula NaOBr·5H2O. It is a yellow-orange solid that is soluble in water. It adopts a monoclinic crystal structure with a Br–O bond length of 1.820 Å.[1] It is the bromine analogue of sodium hypochlorite, the active ingredient in common bleach. In practice the salt is usually encountered as an aqueous solution.

Sodium hypobromite arises by treatment of aqueous solution of bromine with base:[2]

Br2 + 2 NaOH → NaBr + NaOBr + H2O

It can be prepared in situ for use as a reagent, such as in the synthesis of 3-aminopyridine from nicotinamide[3] (Hofmann rearrangement).


  1. ^ Topić, Filip; Marrett, Joseph M.; Borchers, Tristan H.; Titi, Hatem M.; Barrett, Christopher J.; Friščić, Tomislav (2021). "After 200 Years: The Structure of Bleach and Characterization of Hypohalite Ions by Single-Crystal X-Ray Diffraction". Angew. Chem. Int. Ed. 60 (46): 24400–24405. doi:10.1002/anie.202108843. PMID 34293249. S2CID 236199263.
  2. ^ Schmeisser, M. (1963). "Sodium Hypobromite". In Brauer, Georg (ed.). Handbook of Preparative Inorganic Chemistry. Vol. 1 (2nd ed.). New York: Academic Press. pp. 310–311. ISBN 9780323161275.
  3. ^ Allen, C. F. H.; Wolf, Calvin N. (1950). "3-Aminopyridine". Organic Syntheses. 30: 3. doi:10.15227/orgsyn.030.0003; Collected Volumes, vol. 4, p. 45.