Molybdenum Hexacarbonyl
Get Molybdenum Hexacarbonyl essential facts below. View Videos or join the Molybdenum Hexacarbonyl discussion. Add Molybdenum Hexacarbonyl to your PopFlock.com topic list for future reference or share this resource on social media.
Molybdenum Hexacarbonyl
Molybdenum hexacarbonyl
Stereo, skeletal formula of molybdenum hexacarbonyl
Ball and stick model of molybdenum hexacarbonyl
Sample of molybdenum hexacarbonyl
Names
IUPAC name
Hexacarbonylmolybdenum(0)
Systematic IUPAC name
Hexacarbonylmolybdenum[1]
Identifiers
3D model (JSmol)
ChEBI
ChemSpider
ECHA InfoCard 100.034.271
EC Number
  • 237-713-3
3798, 562210
MeSH Hexacarbonylmolybdenum
UN number 3466
Properties
C6MoO6
Molar mass  g·mol-1
Appearance Vivid, white, translucent crystals
Density 1.96 g cm-3
Melting point 150 °C (302 °F; 423 K)
Boiling point 156 °C (313 °F; 429 K)
Structure
Orthogonal
Octahedral
0 D
Thermochemistry
-989.1 kJ mol-1
-2123.4 kJ mol-1
Hazards
Safety data sheet External MSDS
R-phrases (outdated) R26/27/28
S-phrases (outdated) (S1/2), S36/37/39, S45
NFPA 704 (fire diamond)
Flammability code 1: Must be pre-heated before ignition can occur. Flash point over 93 °C (200 °F). E.g. canola oilHealth code 4: Very short exposure could cause death or major residual injury. E.g. VX gasReactivity code 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no codeNFPA 704 four-colored diamond
1
4
0
Related compounds
Related compounds
Chromium hexacarbonyl

Tungsten hexacarbonyl

Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
?N verify (what is ?Y?N ?)
Infobox references

Molybdenum hexacarbonyl (also called molybdenum carbonyl) is the chemical compound with the formula Mo(CO)6. This colorless solid, like its chromium and tungsten analogues, is noteworthy as a volatile, air-stable derivative of a metal in its zero oxidation state.

Structure and properties

Mo(CO)6 adopts an octahedral geometry consisting of six rod-like CO ligands radiating from the central Mo atom. A recurring minor debate in some chemical circles concerns the definition of an "organometallic" compound. Usually, organometallic indicates the presence of a metal directly bonded via a M-C bond to an organic fragment, which must in turn have a C-H bond. By this strict definition, Mo(CO)6 is not organometallic.[]

Preparation

Mo(CO)6 is prepared by the reduction of molybdenum chlorides or oxides under a pressure of carbon monoxide,[] although it would be unusual to prepare this inexpensive compound in the laboratory. The compound is somewhat air-stable and sparingly soluble in nonpolar organic solvents.

Occurrence

Mo(CO)6 has been detected in landfills and sewage plants, the reducing, anaerobic environment being conducive to formation of Mo(CO)6.[2]

Intermediate in inorganic and organometallic synthesis

Mo(CO)6 is a popular reagent in organometallic synthesis[3] because one or more CO ligands can be displaced by other donor ligands.[4] Mo(CO)6, [Mo(CO)3(MeCN)3], and related derivatives are employed as catalysts in organic synthesis for example, alkyne metathesis and the Pauson-Khand reaction.

Mo(CO)6 reacts with 2,2?-bipyridine to afford Mo(CO)4(bipy). UV-photolysis of a THF solution of Mo(CO)6 gives Mo(CO)5(THF).

[Mo(CO)4(piperidine)2]

The thermal reaction of Mo(CO)6 with piperidine affords Mo(CO)4(piperidine)2. The two piperidine ligands in this yellow-colored compound are labile, which allows other ligands to be introduced under mild conditions. For instance, the reaction of [Mo(CO)4(piperidine)2] with triphenyl phosphine in boiling dichloromethane (b.p. ca. 40 °C) gives cis-[Mo(CO)4(PPh3)2]. This cis- complex isomerizes in toluene to trans-[Mo(CO)4(PPh3)2].[5]

[Mo(CO)3(MeCN)3]

Mo(CO)6 also can be converted to its tris(acetonitrile) derivative. The compound serves as a source of "Mo(CO)3". For instance treatment with allyl chloride gives [MoCl(allyl)(CO)2(MeCN)2], whereas treatment with KTp and sodium cyclopentadienide gives [MoTp(CO)3]- and [MoCp(CO)3]- anions, respectively. These anions react with a variety of electrophiles.[6] A related source of Mo(CO)3 is cycloheptatrienemolybdenum tricarbonyl.

Source of Mo atoms

Molybdenum hexacarbonyl is widely used in electron beam-induced deposition technique - it is easily vaporized and decomposed by the electron beam providing a convenient source of molybdenum atoms.[7]

Safety and handling

Like all metal carbonyls, Mo(CO)6 is dangerous source of volatile metal as well as CO.

References

  1. ^ "Hexacarbonylmolybdenum (CHEBI:30508)". Chemical Entities of Biological Interest (ChEBI). UK: European Bioinformatics Institute.
  2. ^ Feldmann, J. (1999). "Determination of Ni(CO)4, Fe(CO)5, Mo(CO)6, and W(CO)6 in Sewage Gas by Using Cryotrapping Gas Chromatography Inductively Coupled Plasma Mass Spectrometry". J. Environ. Monit. 1 (1): 33-37. doi:10.1039/a807277i. PMID 11529076.
  3. ^ Faller, J. W.; Brummond, K. M.; Mitasev, B. (2006). "Hexacarbonylmolybdenum". In Paquette, L. (ed.). Encyclopedia of Reagents for Organic Synthesis. New York: J. Wiley & Sons. doi:10.1002/047084289X.rh004.pub2. ISBN 0471936235.
  4. ^ http://www.chm.bris.ac.uk/teaching-labs/inorganic2ndyear/2004-2005labmanual/Experiment3.pdf Archived March 9, 2008, at the Wayback Machine
  5. ^ Darensbourg, D. J.; Kump, R. L. (1978). "A Convenient Synthesis of cis-Mo(CO)4L2 Derivatives (L = Group 5a Ligand) and a Qualitative Study of Their Thermal Reactivity toward Ligand Dissociation". Inorg. Chem. 17 (9): 2680-2682. doi:10.1021/ic50187a062.
  6. ^ Elschenbroich, C.; Salzer, A. (1992). Organometallics: A Concise Introduction (2nd ed.). Weinheim: Wiley-VCH. ISBN 3-527-28165-7.
  7. ^ Randolph, S. J.; Fowlkes, J. D.; Rack, P. D. (2006). "Focused, Nanoscale Electron-Beam-Induced Deposition and Etching". Critical Reviews of Solid State and Materials Sciences. 31 (3): 55-89. Bibcode:2006CRSSM..31...55R. doi:10.1080/10408430600930438.

Further reading


  This article uses material from the Wikipedia page available here. It is released under the Creative Commons Attribution-Share-Alike License 3.0.

Molybdenum_hexacarbonyl
 



 



 
Music Scenes