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Bromopentacarbonylrhenium(I)

Names
IUPAC name Bromidopentacarbonylrhenium
Identifiers
CAS Number	14220-21-4
3D model (JSmol)	Interactive image
ChemSpider	21171161
ECHA InfoCard	100.034.607
EC Number	238-084-8
PubChem CID	6096983
CompTox Dashboard (EPA)	DTXSID30161971
InChI InChI=1S/5CO.BrH.Re/c5*1-2;;/h;;;;;1H;/q;;;;;;+1/p-1Key: NWJBOTGGBYFKEJ-UHFFFAOYSA-M
SMILES #.#.#.#.#.Br
Properties
Chemical formula	Re(CO)5Br
Molar mass	406.16 g/mol
Appearance	colorless
Melting point	sublimes 85-90 °C (0.2 mm Hg)
Solubility in chlorocarbons	soluble
Hazards
GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H301, H311, H315, H319, H331, H335
Precautionary statements	P261, P264, P270, P271, P280, P301+P310, P302+P352, P304+P340, P305+P351+P338, P311, P312, P321, P322, P330, P332+P313, P337+P313, P361, P362, P363, P403+P233, P405, P501
Except where otherwise noted, data are given for materials in their standard state (at 25 °C , 100 kPa). Y verify (what is  ?) Infobox references

Bromopentacarbonylrhenium(I) is an inorganic compound of rhenium, commonly used for the syntheses of other rhenium complexes.

Preparation

Bromopentacarbonylrhenium(I) is commercially available. It is also easily and inexpensively synthesized by the oxidation of dirhenium decacarbonyl with bromine:

Re₂(CO)₁₀ + Br₂ → 2 ReBr(CO)₅

It was first prepared by the "reductive carbonylation" of rhenium(III) bromide:

ReBr₃ + 2 Cu + 5 CO → BrRe(CO)₅ + 2 CuBr

Copper(I) bromide is a byproduct.

Reactions

Bromopentacarbonylrhenium(I) is a precursor to other rhenium complexes. It reacts with zinc and acetic acid to give pentacarbonylhydridorhenium (HRe(CO)₅).

Re(CO)₅Br + Zn + HO₂CCH₃ → ReH(CO)₅ + ZnBrO₂CCH₃

It also reacts with tetraethylammonium bromide in diglyme to give ₂, an important precursor to compounds containing the rhenium tricarbonyl fragment.

Heating bromopentacarbonylrhenium(I) in water give the triaquo complex:

ReBr(CO)₅ + 3 H₂O → Br + 2 CO

This route avoids the formation of the tetraethylammonium bromide byproduct, which is often difficult to remove from reaction mixtures.

References

1. Steven P. Schmidt; William C. Trogler; Fred Basolo (1990). "Pentacarbonylrhenium Halides". Inorganic Syntheses. Vol. 28. pp. 154–159. doi:10.1002/9780470132593.ch42. ISBN 9780470132593.
2. W. Hieber; Hans Schulten (1939). "XXX. Mitteilung über Metallcarbonyle. Über Rhenium-Kohlenoxyd-Verbindungen". Zeitschrift für anorganische und allgemeine Chemie. 243 (2): 164–173. doi:10.1002/zaac.19392430205.
3. Michael A. Urbancic; John R. Shapley (1990). "Pentacarbonylhydridorhenium". Inorganic Syntheses. Vol. 28. pp. 165–8. doi:10.1002/9780470132593.ch43. ISBN 9780470132593.
4. R. Alberto; A Egli; U. Abram; K. Hegetschweiler; V. Gramlich & P. A. Schubiger (1994). "Synthesis and Reactivity of ₂. Formation and Structural Characterization of the Clusters and by alkaline titration". J. Chem. Soc., Dalton Trans. (19): 2815–2820. doi:10.1039/DT9940002815.
5. N. Lazarova; S. James; J. Babich & J. Zubieta (2004). "A convenient synthesis, chemical characterization and reactivity of Br: the crystal and molecular structure of ". Inorganic Chemistry Communications. 7 (9): 1023–1026. doi:10.1016/j.inoche.2004.07.006.

• Organorhenium compounds
• Carbonyl complexes
• Bromo complexes