rhenium pentachloride
{{chembox
| Watchedfields = changed
| verifiedrevid = 446433733
| ImageFile = ReCl5structure.png
| IUPACName = Rhenium pentachloride
| OtherNames = Rhenium(V) chloride, Rhenium chloride, pentachlororhenium
| Section1 = {{Chembox Identifiers
| CASNo_Ref = {{cascite|correct|??}}
| CASNo = 13596-35-5
| PubChem = 83602
| EINECS = 237-042-6
| ChemSpiderID = 75428
| InChI = 1/5ClH.Re/h5*1H;/q;;;;;+5/p-5/rCl5Re/c1-6(2,3,4)5
| InChIKey = XZQYTGKSBZGQMO-PXGBCINVAP
| StdInChI = 1S/5ClH.Re/h5*1H;/q;;;;;+5/p-5
| StdInChIKey = XZQYTGKSBZGQMO-UHFFFAOYSA-I
| SMILES = Cl[Re](Cl)(Cl)(Cl)Cl
| SMILES_Comment = monomer
| SMILES1 = Cl[Re-]1(Cl)(Cl)(Cl)[Cl+][Re-]([Cl+]1)(Cl)(Cl)(Cl)Cl
| SMILES1_Comment = dimer
}}
| Section2 = {{Chembox Properties
| Formula = ReCl5
| MolarMass = 363.471 g/mol
| Appearance = red-brown
| Density = 4.9 g/cm3, solid
| Solubility = Will react to decompose and release HCl (g)
| MeltingPtC = 220
| BoilingPt = N/A
| pKa =
| MagSus = +1225.0·10−6 cm3/mol
}}
| Section3 = {{Chembox Structure
| MolShape = Octahedral
| CrystalStruct = Monoclinic, mP48; a = 0.924 nm, b = 1.154 nm, c = 1.203 nm, α = 90°, β = 109.1°, γ = 90°
| SpaceGroup = P21/c, No. 14
}}
| Section7 = {{Chembox Hazards
| ExternalSDS = [http://www.alfa.com/webapps/ec120w.pgm?itemnum=43294 MSDS]
| GHSPictograms = {{GHS07}}
| GHSSignalWord = warning
| HPhrases = {{HPhrases|H315|H319|H335}}
| PPhrases = {{PPhrases|P261| P264, |P271|, P280|, P302+P352,| P304+P340,| P305+P351+P338,| P312,| P321,| P332+P313,| P337+P313,| P362|, P403+P233,| P405|P501}}
| GHS_ref = GHS: [https://pubchem.ncbi.nlm.nih.gov/compound/83602 PubChem 83602]
| MainHazards = releases HCl upon hydrolysis
| NFPA-H = 1 | NFPA-R = 0 | NFPA-S = W }}
| Section8 = {{Chembox Related
| OtherAnions = Rhenium pentafluoride
| OtherCations = Osmium pentachloride
| OtherFunction_label = Rhenium chlorides
| OtherFunction = {{ubl
}}
}}
}}
Rhenium pentachloride is an inorganic compound with the formula {{chem2|Re2Cl10}}. This red-brown solid is paramagnetic.{{cite journal |doi=10.1021/ja00534a001 |title=Bridged and Unbridged M2L10 Complexes |date=1980 |last1=Shaik |first1=Sason |last2=Hoffmann |first2=Roald |last3=Fisel |first3=C. Richard |last4=Summerville |first4=Richard H. |journal=Journal of the American Chemical Society |volume=102 |issue=14 |pages=4555–4572 }}
Structure and preparation
Rhenium pentachloride has a bioctahedral structure and can be described as Cl4Re(μ-Cl)2ReCl4. The (μ-Cl)2 part of this formula indicates that two chloride ligands are bridging ligands, i.e. they connect to two Re atoms. The Re-Re distance is 3.74 Å.{{cite journal | doi = 10.1107/S0567740868003316 | title = The crystal structure of ReCl5 | year = 1968 | author = Mucker, K. F. | journal = Acta Crystallographica Section B | volume = 24 | pages = 874 | last2 = Smith | first2 = G. S. | last3 = Johnson | first3 = Q. | issue = 6| bibcode = 1968AcCrB..24..874M | url = http://journals.iucr.org/b/issues/1968/06/00/a06172/a06172.pdf }} The motif is similar to that seen for tantalum pentachloride.
This compound was first prepared in 1933,{{cite journal |author1=Geilmann, Wilhelm |author2=Wrigge, Friedrich W. |author3=Biltz, Wilhelm. | title = Rheniumpentachlorid | language = German | journal = Z. Anorg. Allg. Chem. | year = 1933 | volume = 214 | pages = 244 | doi = 10.1002/zaac.19332140304 | issue = 3}} a few years after the discovery of rhenium. The preparation involves chlorination of rhenium at temperatures up to 900 °C.Roger Lincoln, Geoffrey Wilkinson "Rhenium Pentachloride and Volatile Metal Chlorides by Direct Chlorination Using a Vertical-Tube Reactor" Inorganic Syntheses, 1980, Volume 20, Pages 41–43. {{doi|10.1002/9780470132517.ch11}}. The material can be purified by sublimation.
ReCl5 is one of the most oxidized binary chlorides of Re. It does not undergo further chlorination. ReCl6 has been prepared from rhenium hexafluoride.{{ cite journal | first1 = Farhad | last1 = Tamadon | first2 = Konrad | last2 = Seppelt | title = The Elusive Halides VCl5, MoCl6, and ReCl6 | journal = Angew. Chem. Int. Ed. | year = 2013 | volume = 52 | issue = 2 | pages = 767–769 | doi = 10.1002/anie.201207552 | pmid = 23172658 }} Rhenium heptafluoride is known but not the heptachloride.{{cite journal|doi=10.1021/ic9605736 |title=Stabilization of High Oxidation States in Transition Metals. 2. WCl6 Oxidizes [WF6]−, but Would PtCl6 Oxidize [PtF6]−? An Electrochemical and Computational Study of 5d Transition Metal Halides: [MF6] z versus [MCl6] z (M = Ta to Pt; z = 0, 1−, 2−) |date=1998 |last1=MacGregor |first1=Stuart A. |last2=Moock |first2=Klaus H. |journal=Inorganic Chemistry |volume=37 |issue=13 |pages=3284–3292 }}
Uses and reactions
It degrades in air to a brown liquid.{{cite journal | doi = 10.1039/J19700001617 | title = Some reactions of rhenium(V) chloride | year = 1970 | author = Edwards, D. A. | journal = Journal of the Chemical Society A | pages = 1617 | last2 = Ward | first2 = R. T.}}
Although rhenium pentachloride has no commercial applications, it is of historic significance as one of the early catalysts for olefin metathesis.Ring-opening polymerization of endo and exo-dicyclopentadiene and their 7,8-dihydro derivatives, Hamilton, J.G.; Ivin, K.J.; Rooney, J.J. Journal of Molecular Catalysis 1986, 36, 115. Reduction gives trirhenium nonachloride.
Oxygenation affords the Re(VII) oxychloride:{{Housecroft2nd}}
:ReCl5 + 3 Cl2O → ReO3Cl + 5 Cl2
Comproportionation of the penta- and trichloride gives rhenium tetrachloride.
References
{{Rhenium compounds}}
{{Chlorides}}