Chlorobis(dppe)iron hydride
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| ImageFile1 = HFeCl dppe 2.svg
| ImageSize =
| ImageFile2 = WEQGOOsideon.png
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| IUPACName = Chlorohydridobis(bis-1,2-(diphenylphosphino)ethane)iron(II)
| OtherNames =
|Section1={{Chembox Identifiers
| CASNo = 32490-70-3
| PubChem = 165365653
| SMILES = Cl[FeH-4]56([P+](c1ccccc1)(c2ccccc2)CC[P+]5(c3ccccc3)c4ccccc4)[P+](c1ccccc1)(c2ccccc2)CC[P+]6(c3ccccc3)c4ccccc4
| StdInChI=1S/2C26H24P2.ClH.Fe.H/c2*1-5-13-23(14-6-1)27(24-15-7-2-8-16-24)21-22-28(25-17-9-3-10-18-25)26-19-11-4-12-20-26;;;/h2*1-20H,21-22H2;1H;;/q;;;+1;/p-1
| StdInChIKey=NSXBDVRBULAONI-UHFFFAOYSA-M
}}
|Section2={{Chembox Properties
| C=52|H=49|P=4|Cl=1|Fe=1
| MolarMass = 889.09
| Appearance = red-violet solid
| Density =
| MeltingPtC = 195
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|Section3={{Chembox Hazards
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Chlorobis(dppe)iron hydride is a coordination complex with the formula HFeCl(dppe)2, where dppe is the bidentate ligand 1,2-bis(diphenylphosphino)ethane. It is a red-violet solid. The compound has attracted much attention as a precursor to dihydrogen complexes.{{cite journal |vauthors=Morris RH |title=Dihydrogen, Dihydride and in Between: Nmr and Structural Properties of Iron Group Complexes |journal=Coord. Chem. Rev. |year=2008 |volume=2252 |issue=21–22 |pages=2381–2394 |doi=10.1016/j.ccr.2008.01.010}}
Structure
The complex exhibits octahedral molecular geometry. The chloride and hydride ligands are mutually trans.Lee, J.; Jung, G.; Lee, S. W. Structure of trans-chlorohydridobis(diphenylphosphinoethane)iron(II). Bull. Korean. Chem. 1998, 19, 267. {{ISSN|0253-2964}} The bond distances between the iron metal atom and the coordinating ligands are given by the following:
| class="toccolours" border="1" style="margin: 1em; border-collapse: collapse;" | |
| Bond | Bond distance |
| Fe-P1 | 2.238 |
| Fe-P2 | 2.256 |
| Fe-P3 | 2.236 |
| Fe-P4 | 2.255 |
| Fe-Cl | 2.404 |
| Fe-H | 1.313 |
Synthesis and reactions
The compound is synthesized according to the following idealized reaction:{{cite book|author1=Giannoccaro, P. |author2=Sacco, A. |title=Inorganic Syntheses |chapter=Bis[Ethylenebis(Diphenylphosphine)]-Hydridoiron Complexes |journal=Inorg. Synth.|year=1977|volume=17|pages=69–71|doi=10.1002/9780470132487.ch19|isbn=9780470132487 }}
:FeCl2 + 2 dppe + Na[BH4] → NaCl + ½ B2H6 + HFeCl(dppe)2
In the course of this conversion, high-spin complex FeCl2(dppe)2 converts to low-spin HFeCl(dppe)2.
The complex HFeCl[(dppe)2 exhibits a number of reactions associated with the remaining Fe-Cl bond. Reaction of the complex with sodium borohydride gives the dihydride complex:
:HFeCl(dppe)2 + NaBH4 → H2Fe(dppe)2 + NaCl + "BH3"
Removal of chloride using sodium tetrafluorborate under and atmostphere of hydrogen or nitrogen gives the dinitrogen and dihydrogen complexes:{{cite journal|vauthors=Bautista MT, Bynum LD, Schauer CK |title=Synthesis of η2-Dihydrogen Complex, trans-
:HFeCl(dppe)2 + NaBF4 + N2 → [HFe(N2)(dppe)2]BF4 + NaCl
:HFeCl(dppe)2 + NaBF4 + H2 → [HFe(H2)(dppe)2]BF4 + NaCl