Nickel(II) bromide

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Nickel(II) bromide
Kristallstruktur Cadmiumiodid.png
Bromid nikelnatý.PNG
Names
IUPAC name
Nickel(II) bromide
Other names
Nickel dibromide,
Nickel bromide,
Nickelous bromide
Identifiers
  • 13462-88-9 Anhydrous checkY
  • 13596-19-5 dihydrate ☒N
  • 7789-49-3 trihydrate ☒N
  • 18721-96-5 hexahydrate ☒N
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.033.318 Edit this at Wikidata
UNII
  • InChI=1S/2BrH.Ni/h2*1H;/q;;+2/p-2 ☒N
    Key: IPLJNQFXJUCRNH-UHFFFAOYSA-L ☒N
  • [Ni+2].[Br-].[Br-]
Properties
NiBr2
Molar mass 218.53 g/mol
Appearance yellow-brown crystals
Odor odorless
Density 5.098 g/cm3[1]
Melting point 963 °C (1,765 °F; 1,236 K) sublimes
113 g/100ml (0 °C)
122 g/100ml (10 °C)
134 g/100ml (25 °C)[2]
144 g/100ml (40 °C)
155 g/100ml (100 °C)
+5600.0·10−6 cm3/mol
Hazards
Main hazards Irritant, corrosive
NFPA 704 (fire diamond)
1
0
0
Flash point Non-flammable
Related compounds
Other anions
 nickel(II) fluoride
nickel(II) chloride
nickel(II) iodide
Other cations
 cobalt(II) bromide
copper(II) bromide
palladium(II) bromide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
☒N  (what is checkY☒N ?)
Infobox references

Nickel(II) bromide is the name for the inorganic compounds with the chemical formula NiBr2(H2O)x. The value of x can be 0 for the anhydrous material, as well as 2, 3, or 6 for the three known hydrate forms. The anhydrous material is a yellow-brown solid which dissolves in water to give blue-green hexahydrate (see picture).

Structure[]

The structure of the nickel bromides varies with the degree of hydration. In all of these cases, the nickel(II) ion adopts an octahedral molecular geometry.

  • Anhydrous NiBr2 adopts the cadmium chloride structure.[3][4] The interatomic distance for Ni-Br is 2.52—2.58 Å.[4]
  • The structure of the trihydrate has not been confirmed by X-ray crystallography. It is assumed to adopt a chain structure.[5]
  • The di- and hexahydrates adopt structures akin to those for the corresponding chlorides. The dihydrate consists of a linear chain, whereas the hexahydrate features isolated trans-[NiBr2(H2O)4] molecules together with two noncoordinated water molecules.

Reactions and uses[]

NiBr2 has Lewis acid character. NiBr2 is also used to prepare catalysts for cross-coupling reactions and various carbonylations.[3]

Empirically, NiBr2-glyme has shown increased activity compared to that of NiCl2-glyme for some transformations.[6]

NiBr2-catalyzed cross-coupling reaction.

Safety[]

Nickel(II) is toxic and suspected to be a cancer agent.[3]

References[]

  1. ^ http://chemdat.merck.de/documents/sds/emd/deu/de/8181/818174.pdf
  2. ^ http://chemister.ru/Database/properties-en.php?dbid=1&id=3859
  3. ^ a b c Luh, Tien-Yau; Kuo, Chi-Hong (2001-01-01). Encyclopedia of Reagents for Organic Synthesis. John Wiley & Sons, Ltd. doi:10.1002/047084289X.rn009. ISBN 9780470842898.
  4. ^ a b Wakita, Hisanobu; Ichihashi, Mitsuyoshi; Mibuchi, Takeharu; Masuda, Isao (1982-03-01). "The Structure of Nickel(II) Bromide in Highly Concentrated Aqueous Solution by X-Ray Diffraction Analysis". Bulletin of the Chemical Society of Japan. 55 (3): 817–821. doi:10.1246/bcsj.55.817. ISSN 0009-2673.
  5. ^ DeFotis, G. C.; Goodey, J. R.; Narducci, A. A.; Welch, M. H. "NiBr2·3H2O, a lower dimensional antiferromagnet" Journal of Applied Physics (1996), 79(8, Pt. 2A), 4718-4720. doi:10.1063/1.361651
  6. ^ Konev, Mikhail O.; Hanna, Luke E.; Jarvo, Elizabeth R. (2016-06-01). "Intra- and Intermolecular Nickel-Catalyzed Reductive Cross-Electrophile Coupling Reactions of Benzylic Esters with Aryl Halides". Angewandte Chemie International Edition. 55 (23): 6730–6733. doi:10.1002/anie.201601206. PMID 27099968.
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