molybdenum hexacarbonyl
{{Chembox
|Verifiedfields = changed
|Watchedfields = changed
|verifiedrevid = 268875245
|ImageFileL1 = Molybdenum-hexacarbonyl-2D.png
|ImageFileL1_Ref = {{chemboximage|correct|??}}
|ImageSizeL1 = 121
|ImageNameL1 = Stereo, skeletal formula of molybdenum hexacarbonyl
|ImageFileR1 = Molybdenum-hexacarbonyl-from-xtal-3D-balls.png
|ImageFileR1_Ref = {{chemboximage|correct|??}}
|ImageSizeR1 = 121
|ImageNameR1 = Ball and stick model of molybdenum hexacarbonyl
|ImageFile2 = Mocarbonyl.JPG
|ImageFile2_Ref = {{chemboximage|correct|??}}
|ImageSize2 = 244
|ImageName2 = Sample of molybdenum hexacarbonyl
|IUPACName = Hexacarbonylmolybdenum(0)
|SystematicName = Hexacarbonylmolybdenum{{Cite web | title = Hexacarbonylmolybdenum (CHEBI:30508) | url = https://www.ebi.ac.uk/chebi/searchId.do?chebiId=30508 | work = Chemical Entities of Biological Interest (ChEBI) | location = UK | publisher = European Bioinformatics Institute }}
|Section1={{Chembox Identifiers
|CASNo = 13939-06-5
|CASNo_Ref = {{cascite|correct|CAS}}
|PubChem = 98885
|ChemSpiderID = 21428397
|ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
|EINECS = 237-713-3
|UNNumber = 3466
|MeSHName = Hexacarbonylmolybdenum
|ChEBI_Ref = {{ebicite|correct|EBI}}
|ChEBI = 30508
|Gmelin = 3798, 562210
|SMILES = O=C=[Mo](=C=O)(=C=O)(=C=O)(=C=O)=C=O
|StdInChI = 1S/6CO.Mo/c6*1-2;
|StdInChI_Ref = {{stdinchicite|changed|chemspider}}
|StdInChIKey = KMKBZNSIJQWHJA-UHFFFAOYSA-N
|StdInChIKey_Ref = {{stdinchicite|changed|chemspider}}
}}
|Section2={{Chembox Properties
|C=6 | Mo=1 | O=6
|Appearance = Vivid, white, translucent crystals
|Density = 1.96 g cm−3
|MeltingPtC = 150
|BoilingPtC = 156
|Solubility = insoluble
|SolubleOther = slightly soluble in THF, diglyme, acetonitrile{{cite book |last1= Faller|first1= John W.|last2= Brummond|first2= Kay M.|last3=Mitasev |first3= Branko|date= 15 September 2006|title= Encyclopedia of Reagents for Organic Synthesis|chapter=Hexacarbonylmolybdenum |url= https://onlinelibrary.wiley.com/doi/10.1002/047084289X.rh004.pub2|location= |publisher= Wiley|page= |doi=10.1002/047084289X |hdl= 10261/236866|isbn=9780470842898}}
}}
|Section3={{Chembox Structure
|CrystalStruct = Orthogonal
|Coordination = Octahedral
|Dipole = 0 D
}}
|Section4={{Chembox Thermochemistry
|DeltaHf = −989.1 kJ mol−1
|DeltaHc = −2123.4 kJ mol−1
}}
|Section5={{Chembox Hazards
|ExternalSDS = [https://ereztech.com/wp-content/uploads/chemical_sds/SDS-MO9065.pdf External MSDS]
|GHSPictograms = {{GHS06}}
|GHSSignalWord = Danger
|HPhrases = {{H-phrases|300|310|315|319|330|413}}
|PPhrases = {{P-phrases|261|271|280|304+340+311|405|501}}
|NFPA-H = 4
|NFPA-F = 1
|NFPA-R = 0
}}
|Section6={{Chembox Related
|OtherCompounds = Chromium hexacarbonyl
Tungsten hexacarbonyl
Seaborgium hexacarbonyl{{Cite journal | doi = 10.1126/science.1255720| pmid = 25237098| title = Synthesis and detection of a seaborgium carbonyl complex| journal = Science| volume = 345| issue = 6203| pages = 1491–3| year = 2014| last1 = Even | first1 = J.| last2 = Yakushev | first2 = A.| last3 = Dullmann | first3 = C. E.| last4 = Haba | first4 = H.| last5 = Asai | first5 = M.| last6 = Sato | first6 = T. K.| last7 = Brand | first7 = H.| last8 = Di Nitto | first8 = A.| last9 = Eichler | first9 = R.| last10 = Fan | first10 = F. L.| last11 = Hartmann | first11 = W.| last12 = Huang | first12 = M.| last13 = Jager | first13 = E.| last14 = Kaji | first14 = D.| last15 = Kanaya | first15 = J.| last16 = Kaneya | first16 = Y.| last17 = Khuyagbaatar | first17 = J.| last18 = Kindler | first18 = B.| last19 = Kratz | first19 = J. V.| last20 = Krier | first20 = J.| last21 = Kudou | first21 = Y.| last22 = Kurz | first22 = N.| last23 = Lommel | first23 = B.| last24 = Miyashita | first24 = S.| last25 = Morimoto | first25 = K.| last26 = Morita | first26 = K.| last27 = Murakami | first27 = M.| last28 = Nagame | first28 = Y.| last29 = Nitsche | first29 = H.| last30 = Ooe | first30 = K.| display-authors = 29| bibcode = 2014Sci...345.1491E| s2cid = 206558746}} {{subscription required}}
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Molybdenum hexacarbonyl (also called molybdenum carbonyl) is the chemical compound with the formula Mo(CO)6. This colorless solid, like its chromium, tungsten, and seaborgium 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.
Like many metal carbonyls, Mo(CO)6 is generally prepared by "reductive carbonylation", which involves reduction of a metal halide with under an atmosphere of carbon monoxide. As described in a 2023 survey of methods "most cost-effective routes for the synthesis of group 6 hexacarbonyls are based on the reduction of the metal chlorides (CrCl3, MoCl5 or WCl6) with magnesium, zinc or aluminium powders... under CO pressures".{{cite journal |doi=10.1016/j.ccr.2022.214983|title=Group 6 Carbonyl Complexes of N,O,P-Ligands as Precursors of High-Valent Metal-Oxo Catalysts for Olefin Epoxidation |year=2023 |last1=Bruno |first1=Sofia M. |last2=Valente |first2=Anabela A. |last3=Gonçalves |first3=Isabel S. |last4=Pillinger |first4=Martyn |journal=Coordination Chemistry Reviews |volume=478 |page=214983 |s2cid=255329673 |doi-access=free |hdl=10773/40120 |hdl-access=free }}
Occurrence
Mo(CO)6 has been detected in landfills and sewage plants, the reducing, anaerobic environment being conducive to formation of Mo(CO)6.{{cite journal | last= Feldmann |first=J. | title = 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 | journal = Journal of Environmental Monitoring | year = 1999 | volume = 1 | issue = 1 | pages = 33–37 | doi = 10.1039/a807277i | pmid=11529076}}
Inorganic and organometallic research
Molybdenum hexacarbonyl is a popular reagent in academic research.{{cite encyclopedia | last1= Faller |first1=J. W. |last2=Brummond |first2=K. M. |last3=Mitasev |first3=B. | chapter = Hexacarbonylmolybdenum | encyclopedia = Encyclopedia of Reagents for Organic Synthesis | editor-first = L. |editor-last=Paquette | year = 2006 | publisher = J. Wiley & Sons | location = New York | doi = 10.1002/047084289X.rh004.pub2 |isbn=0471936235}}
One or more CO ligands can be displaced by other ligands.{{cite web |url=http://www.chm.bris.ac.uk/teaching-labs/inorganic2ndyear/2004-2005labmanual/Experiment3.pdf |title=THE SYNTHESIS & SPECTROSCOPIC CHARACTERISATION OF METAL CARBONYL COMPLEXES |website=www.chm.bris.ac.uk |archive-url=https://web.archive.org/web/20080309162142/http://www.chm.bris.ac.uk/teaching-labs/inorganic2ndyear/2004-2005labmanual/Experiment3.pdf |archive-date=March 9, 2008}} 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)<sub>4</sub>(piperidine)<sub>2</sub>]=
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].{{cite journal | last1 = Darensbourg | first1 = D. J. | last2 = Kump | first2 = R. L. | title = A Convenient Synthesis of cis-Mo(CO)4L2 Derivatives (L = Group 5a Ligand) and a Qualitative Study of Their Thermal Reactivity toward Ligand Dissociation |journal = Inorg. Chem. | year = 1978 | volume = 17 | issue = 9 | pages = 2680–2682 | doi = 10.1021/ic50187a062 }}
=[Mo(CO)<sub>3</sub>(MeCN)<sub>3</sub>]=
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.{{cite book | last1= Elschenbroich |first1=C. |last2=Salzer |first2=A. | title = Organometallics: A Concise Introduction | edition = 2nd | year = 1992 | publisher = Wiley-VCH | location = Weinheim | isbn = 3-527-28165-7 }} 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.{{ cite journal | last1 = Randolph | first1 = S. J. | last2 = Fowlkes | first2 = J. D. | last3 = Rack | first3 = P. D. | title = Focused, Nanoscale Electron-Beam-Induced Deposition and Etching | journal = Critical Reviews of Solid State and Materials Sciences | volume = 31 | year = 2006 | issue = 3 | pages = 55–89 | doi = 10.1080/10408430600930438 | bibcode = 2006CRSSM..31...55R | s2cid = 93769658 }}
Safety and handling
Like all metal carbonyls, Mo(CO)6 is a dangerous source of volatile metal as well as CO.
References
{{reflist}}
Further reading
- {{cite journal | last= Marradi |first=M. | title = Synlett Spotlight 119: Molybdenum Hexacarbonyl
[ Mo(CO)6] | journal = Synlett | year = 2005 | volume = 2005 | issue = 7 | pages = 1195–1196 | doi = 10.1055/s-2005-865206 | url = https://www.thieme-connect.de/ejournals/pdf/synlett/doi/10.1055/s-2005-865206.pdf | doi-access = free}} - {{cite journal | last1= Feldmann |first1=J. |last2=Cullen |first2=W. R. | title = Occurrence of Volatile Transition Metal Compounds in Landfill Gas: Synthesis of Molybdenum and Tungsten Carbonyls in the Environment | journal = Environ. Sci. Technol. | year = 1997 | volume = 31 | issue = 7 | pages = 2125–2129 | doi = 10.1021/es960952y |bibcode=1997EnST...31.2125F}}
- {{cite journal | last1= Feldmann |first1=J. |last2=Grümping |first2=R. |last3=Hirner |first3=A. V. | title = Determination of Volatile Metal and Metalloid Compounds in Gases from Domestic Waste Deposits with GC/ICP-MS | journal = Fresenius' J. Anal. Chem. | year = 1994 | volume = 350 | issue = 4–5 | pages = 228–234 | doi = 10.1007/BF00322474 |s2cid=95405500 }}
{{Molybdenum compounds}}
Category:Molybdenum(0) compounds