Manganese(III) fluoride: Difference between revisions

| verifiedrevid = 400294796

| Name = Manganese(III) fluoride

| ImageFile =MnF3structure.jpg

| ImageName = Manganese(III) fluoride

| IUPACName = Manganese(III) fluoride

| OtherNames = Manganese trifluoride, manganic fluoride

| Section1 = {{Chembox Identifiers

| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}

| PubChem = 522682

| RTECS = OP0882600

| Section2 = {{Chembox Properties

| Formula = MnF₃

| MolarMass = 111.938 g/mol

| Appearance = purple-pink powder

| Density = 3.54 g/cm³

| Solubility = hydrolysis

| MeltingPt = > 600 °C (decomp)

| Section3 = {{Chembox Structure

| Coordination = distorted octahedral

| CrystalStruct = [[Monoclinic]], [[Pearson symbol|mS48]]

| SpaceGroup = C2/c, No. 15

| Section7 = {{Chembox Hazards

| MainHazards = toxic fumes

| RPhrases = 8-20/21/22-36/37/38

| SPhrases = 17-26-36/37/39

| Section8 = {{Chembox Related

| OtherAnions = [[manganese(III) oxide]], [[manganese(III) acetate]]

| OtherCations = [[chromium(III) fluoride]], [[iron(III) fluoride]]. [[cobalt(III) fluoride]]

| OtherCpds = [[manganese(II) fluoride]], [[manganese(IV) fluoride]]

'''Manganese(III) fluoride''' (also known as '''Manganese trifluoride''') is the [[inorganic compound]] with the formula MnF₃. This red/purplish solid is useful for converting [[hydrocarbon]]s into [[fluorocarbon]]s, i.e., it is a fluorination agent.<ref>Burley, G. A.; Taylor, R. "Manganese(III) fluoride" in Encyclopedia of Reagents for Organic Synthesis (Ed: L. Paquette) 2004, J. Wiley & Sons, New York. {{DOI|10.1002/047084289}}</ref> It also forms a hydrate.

===Synthesis===

:MnF₂ + 0.5 F₂ &rarr; MnF₃

It can also be prepared by the reaction of elemental fluorine with a manganese(II) halide at ~250 °C.<ref name="shap">Inorganic chemistry, Catherine E. Housecroft, A.G. Sharpe, pp.711-712, section ''Manganese (III)'' , [http://books.google.co.uk/books?id=3sy4ZAP4EGAC&dq googlebooks link]</ref>

In the crystalline state, MnF₃ resembles [[vanadium(III) fluoride]]: both feature octahedal metal centers with the same average M-F bond distances. In the Mn compound, however, is distorted (and hence a [[monoclinic]] unit cell vs. a higher symmetry one) due to the [[Jahn-Teller effect]], with pairs of Mn-F distances of 1.79, 1.91, 2.09 Å.<ref>Wells, A.F. (1984) Structural Inorganic Chemistry, Oxford: Clarendon Press. ISBN 0-19-855370-6.</ref><ref>{{cite journal | author = Hepworth, M. A.; Jack, K. H.; [[Ronald Sydney Nyholm|Nyholm]], R. S. | title = Interatomic Bonding in Manganese Trifluoride | journal = [[Nature (journal)|Nature]] | year = 1957 | volume = 179 | pages = 211–212 | doi = 10.1038/179211b0 | issue = 4552}}</ref><ref>{{cite journal

| title = The crystal structure of manganese trifluoride, MnF₃

| author = M. A. Hepworth, K. H. Jack

| journal = Acta Crystallographica

The hydrate MnF₃^.3H₂O is obtained by crystallisation of MnF₃ from hydrofluoric acid. The hydrate is unusual in that it forms two different structures (both based on [Mn(H₂O)₄F₂]⁺ [Mn(H₂O)₂F₄]^- ), which have [[space group]]s P2₁/c and P2₁/a.<ref>Structures of two polymorphs of MnF3·3H2O , Michel Molinier and Werner Massa , Journal of Fluorine Chemistry , Volume 57, Issues 1-3, April–June 1992, pp.139-146 , [http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TGD-42H1S9S-21&_user=10&_coverDate=06/30/1992&_rdoc=1&_fmt=high&_orig=search&_sort=d&_docanchor=&view=c&_searchStrId=1370631000&_rerunOrigin=google&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=aadd1956f6c1e3401bf08c1e14c2ee88 online abstract via ''www.sciencedirect.com'']</ref>

MnF₃ reacts with [[sodium fluoride]] to give the octahedral hexafluorate anion:<ref name="shap"/>:

Other reaction conditions give compounds with anion formula MnF₅^2- or MnF₄^-. These anions are chain and layer structures respectively, with bridging fluorine. Manganese remains 6 coordinate, octahedral, and trivalent in all these materials.<ref name="shap"/>

Manganese(III) fluoride fluorinates organic compounds including aromatic hydrocarbons,<ref>[http://notes.fluorine1.ru/contents/Nov98/Notes/letters/letter1.html Fluorination of p-chlorobenzotrifluoride by manganese trifluoride] A. Kachanov, V. Kornilov, V.Belogay , Fluorine Notes :Vol. 1 (1) November–December 1998 , via ''notes.fluorine1.ru''</ref> cyclobutenes,<ref>Fluorination of fluoro-cyclobutene with high-valency metal fluoride m Junji Mizukado, Yasuhisa Matsukawa, Heng-dao Quan, Masanori Tamura, Akira Sekiya , Journal of Fluorine Chemistry

Volume 127, Issue 1, January 2006, Pages 79-84 , [http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TGD-4HNS6P9-2&_user=10&_coverDate=01/31/2006&_rdoc=1&_fmt=high&_orig=search&_sort=d&_docanchor=&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=1be7e0e886c36ce120b73ca1d2e37710 online abstract via ''www.sciencedirect.com'']</ref> and fullerenes.<ref>Fluorination of the cubic and hexagonal C60 modifications by crystalline manganese trifluoride , Physics of the Solid State , Volume 44, Number 4 , 4/2002 , pp.629-630 , V.É. Aleshina, A.Ya. Borshchevskii, E.V. Skokan, I.V. Arkhangel’skii, A.V. Astakhov, N.B. Shustova , [http://www.springerlink.com/content/g563v8hl256uh2l5/ online abstract via ''www.springerlink'']</ref>

On heating, MnF₃ decomposes to [[manganese(II) fluoride]].<ref>[http://www.1911encyclopedia.org/Manganese Manganese; section ''Manganic Salts'' ] via ''www.1911encyclopedia.org''</ref><ref>In situ time-resolved X-ray diffraction study of manganese trifluoride thermal decomposition , J.V. Raua, V. Rossi Albertinib, N.S. Chilingarova, S. Colonnab, U. Anselmi Tamburini, Journal of Fluorine Chemistry 4506 (2001) 1–4 , [http://ftp.esrf.eu/pub/UserReports/21876_A.pdf online version]</ref>

==Related Mn(III) compounds==

Other manganese(III) compounds include manganese(III) acetate (CAS# 993-02-2), [[manganese acetylacetonate]] (CAS# 14284-89-0), Both are employed as oxidants in [[organic synthesis]]. MnF₃ is Lewis acidic and forms a variety of derivatives. Two examples are K₂MnF₃(SO₄)<ref>{{cite journal | author = Bhattacharjee, M. N; Chaudhuri, M. K. | title = Dipotassium Trifluorosulfatomanganate(III) | journal = [[Inorg. Synth.]] | year = 1990 | volume = 27 | pages = 312–313 | doi = 10.1002/9780470132586.ch61}}</ref> and K₂MnF₅.

==Safety considerations==

Like other reactive inorganic fluorides, MnF₃ should be stored in a polyethylene bottle and contact with skin or any other moist area avoided due to the formation of [[Hydrofluoric acid]] on hydrolysis.

[[Cobalt(III) fluoride|CoF₃]], another fluorinating agent based on a transition metal in an oxidising +3 state.

{{reflist|2}}

*[http://acta.chem-soc.si/46/46-2-229.pdf Novel syntheses of some binary fluorides: the role of anhydrous hydrogen fluoride] Acta Chim. Slov. 1999, 46(2), pp.&nbsp;229–238 , Zoran Mazej, Karel Lutar and Boris Žemva

*Knudsen Cell mass spectrometry study of Manganese Trifluoride vaporisation , High temperature corrosion and materials chemistry IV: proceedings of the International Symposium , pp.&nbsp;521–525 , [http://books.google.co.uk/books?id=qsxW_N7DFykC&pg=PA521&lpg=PA521&dq=mnf3&source=bl&ots=FSkqFmbboo&sig=VSGSmLn4V_Re5rRMR_urHwNqLts&hl=en&ei=U9kXTL6bFYmM0gSno73FCw&sa=X&oi=book_result&ct=result&resnum=5&ved=0CCEQ6AEwBDgU#v=onepage&q=mnf3&f=false google books]

*[http://www.npi.gov.au/database/substance-info/profiles/44.html National Pollutant Inventory: Fluoride and compounds fact sheet]

*[http://www.npi.gov.au/database/substance-info/profiles/52.html National Pollutant Inventory: Manganese and compounds Fact Sheet]

[[Category:Manganese compounds]]

[[ar:فلوريد المنغنيز الثلاثي]]

[[pl:Fluorek manganu(III)]]

[[pt:Fluoreto de manganês (III)]]

[[simple:Manganese(III) fluoride]]

[[zh:三氟化錳]]