Nickel(II) bromide

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).

Nickel(II) bromide
Names
IUPAC name
Nickel(II) bromide
Other names
Nickel dibromide,
Nickel bromide,
Nickelous bromide
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.033.318
UNII
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)
Flammability code 0: Will not burn. E.g. waterHealth code 1: Exposure would cause irritation but only minor residual injury. E.g. turpentineReactivity code 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no code
0
1
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 verify (what is YN ?)
Infobox references

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. 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. 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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