查看“︁二苯铬”︁的源代码

{{chembox
|   Name = 二苯铬
|   ImageFileL1 = Bis(benzene)chromium-2D-skeletal.png
|   ImageSizeL1 = 100px
|   ImageNameL1 = Bis(benzene)chromium
|   ImageFileR1 = Bis(benzene)chromium-from-xtal-2006-3D-balls-A.png
|   ImageSizeR1 = 130px 
|   ImageNameR1 = Bis(benzene)chromium
|   ImageFile2 = Bis(benzene)chromium_1.jpg
|   ImageSize2 = 250 px
|   ImageName2 = Bis(benzene)chromium (sublimated, under nitrogen)
|   IUPACName = Bis(benzene) chromium
|   OtherNames = di(benzene) chromium
| Section1 = {{Chembox Identifiers
| CASNo_Ref = {{cascite|correct|??}}
| CASNo = 1271-54-1
| RTECS = GB5850000
  }}
| Section2 = {{Chembox Properties
|   Formula = (C<sub>6</sub>H<sub>6</sub>)<sub>2</sub>Cr
|   MolarMass = 208.22
|   Appearance = 深褐色晶体[https://www.sigmaaldrich.com/US/en/product/aldrich/493651]
|   Density =1.519 g·cm<sup>−3</sup><ref name="Römpp">{{RömppOnline|ID=RD-03-01736|Name=Chrom-organische Verbindungen|Abruf=2014-04-04}}</ref>
|   Solubility = 不溶
|   SolubleOther = 可溶于[[苯]]，难溶于[[乙醚]]<ref name="eros">J. W. Herndon, ''Dibenzenechromium''. In ''e-EROS Encyclopedia of Reagents for Organic Synthesis'', 2001, Wiley, {{DOI|10.1002/047084289X.rd020}}.</ref>
|   MeltingPt = 284-285 °C<ref name="Römpp" />
|   SublimationConditions =150 °C（真空中）<ref name="Römpp" />
  }}
| Section3 = {{Chembox Structure
|   Coordination = 伪[[八面体]]
|   CrystalStruct =
|   Dipole = 0 [[德拜|D]]
  }}
| Section7 = {{Chembox Hazards
|   ExternalMSDS =
|   MainHazards = 易燃
|   FlashPt = 180 °F
|   RPhrases = 11
|   SPhrases = 16-33
  }}
| Section8 = {{Chembox Related
|   OtherCpds = [[二茂铁]]<br />[[二茂铬]]
  }}
}}
'''二苯合铬'''是一种[[有机金属化学|有机金属化合物]]，[[化学式]] (C<sub>6</sub>H<sub>6</sub>)<sub>2</sub>Cr。在空气中易[[氧化]]，不溶于[[水]]，微溶于[[乙醚]]、[[石油醚]]和[[苯]]。

== 历史==
二苯合铬是在1955年由[[恩斯特·奥托·菲舍尔]]和{{link-de|Walter Hafner|Walter Hafner (Chemiker)}}首次成。<ref>{{ZNaturforsch |Serie=B |Autor=E. O. Fischer, W. Hafner |Titel=Di-benzol-chrom. Über Aromatenkomplexe von Metallen |Jahr=1955 |Startseite=665 |Endseite=668}}</ref>他们的方法之后被称为“Fischer-Hafner法”。<ref>{{cite book|author=Dietmar Seyferth|title=Bis(benzene)chromium. 2. Its Discovery by E. O. Fischer and W. Hafner and Subsequent Work by the Research Groups of E. O. Fischer, H. H. Zeiss, F. Hein, C. Elschenbroich, and Others.|date=2002 |pages=2800–2820 |DOI=10.1021/om020362a}}</ref>恩斯特·奥托·菲舍尔在1973和[[杰弗里·威尔金森]]一起活动了[[诺贝尔化学奖]]，来表彰他在夹心化合物化学方面的工作（阐明[[二茂铁]]的结构和二苯铬的合成）。二苯铬的样品是{{le|Deutsches Museum Bonn}}存货的一部分。<ref>Deutsches Museum Bonn: [http://www.deutsches-museum.de/en/bonn/sammlungen/elementares/01/02/dibenzolchrom-und-ferrocen/ ''Dibenzolchrom und Ferrocen''] {{Wayback|url=http://www.deutsches-museum.de/en/bonn/sammlungen/elementares/01/02/dibenzolchrom-und-ferrocen/ |date=20160119171120 }}, abgerufen am 16. April 2018.</ref>

== 制备 ==
[[File:Bis(benzene)chromium 2.jpg|thumb|left|惰性气体下的升华二苯铬晶体]]
二苯铬需要在无氧条件下制备（[[舒伦克线]]）。它的首次合成是Fischer-Hafner法，也就是将[[三氯化铬]]、[[铝]]和[[苯]]在[[三氯化铝]]存在下反应而成。这会形成对空气稳定<ref name="Elschenbroich">{{cite book|author=Christoph Elschenbroich|title=Organometallchemie|edition=6|publisher=Vieweg+Teubner|date=2008|ISBN=9783835101678|location=Wiesbaden}}</ref>的阳离子。之后，它被[[连二亚硫酸钠]]还原，生成二苯铬。<ref>[[Georg Brauer]] (Hrsg.) u.&nbsp;a.: ''Handbuch der Präparativen Anorganischen Chemie.'' 3., umgearbeitete Auflage. Band III, Ferdinand Enke, Stuttgart 1981, ISBN 3-432-87823-0, S.&nbsp;1840.</ref> 

:<chem>CrCl3 + \frac{2}{3}Al + AlCl3 + 2C6H6 -> [Cr(C6H6)2]AlCl4 + \frac{2}{3}AlCl3</chem>
:<chem>[Cr(C6H6)2]AlCl4 + \frac{1}{2}Na2S2O4 -> [Cr(C6H6)2] + NaAlCl4 + SO2 ^</chem>

== 性质==
[[File:Bis(benzene)chromium-from-xtal-2006-3D-balls-A.png|thumb|left|X射线衍射数据描述的固体二苯铬结构<ref>{{cite book|author=Konstantin A. Lyssenko ''et al.''|title=Estimation of the Barrier to Rotation of Benzene in the (η<sup>6</sup>-C<sub>6</sub>H<sub>6</sub>)<sub>2</sub>Cr Crystal via Topological Analysis of the Electron Density Distribution Function|date=2006|pages=6545–6551|DOI=10.1021/jp057516v}}</ref>]]

=== 物理性质 ===
二苯铬有18个[[价电子]]，没有不成对电子，所以也没有[[磁矩]]。不过它的阳离子（17个价电子）有不成对电子，磁矩为 1.77 [[玻尔磁子]]。<ref name="Elschenbroich"/>

==化学性质==
二苯铬可被[[羰基化]]成[[半夹心化合物]][[三羰基苯铬]]。<ref>Fischer, Ernst Otto; Őfele, Karl. (1957). “Über Aromatenkomplexe von Metallen, XIII Benzol-Chrom-Tricarbonyl,” Chemische Berichte, 90, 2532-5.  {{doi|10.1002/cber.19570901117}}.</ref>

== 用处==
二苯铬在[[有机合成]]中用作[[脱氢]][[催化剂]]。<ref name="eros"/>

== 扩展阅读 ==
* Historische Würdigung: Wolfgang A. Herrmann: ''Dibenzechromium: Chemistry only for Chemists?'', [[Z. Anorg. Allg. Chem.]], 2012, S.&nbsp;1245–1247; {{DOI|10.1002/zaac.201210011}}.

==参考资料==
{{reflist}}
{{鉻化合物}}
[[Category:有机铬化合物]]
[[Category:夹心化合物]]
[[Category:1950年代发现的物质]]
[[Category:苯配合物]]