Methylthioirontricarbonyl dimer
Chemical compound
From Wikipedia, the free encyclopedia
Methylthioirontricarbonyl dimer, also known as methanethiolatoirontricarbonyl dimer, is an organometallic compound with the formula Fe2(SCH3)2(CO)6. It is a red volatile solid that is classified as a transition metal thiolate complex. It exists as air-stable red crystals with two isomers, where the methyl groups are either anti (isomer A) or syn (isomer B) with respect to each other.[1]
2(CO)6.svg)
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2(CO)6.jpg) | |
| Names | |
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| Other names
Methanethiolatoirontricarbonyl dimer | |
| Identifiers | |
3D model (JSmol) |
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| ECHA InfoCard | 100.035.396 |
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PubChem CID |
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| Properties | |
| C8H6Fe2O6S2 | |
| Molar mass | 373.94 g/mol |
| Appearance | red crystals |
| Melting point | 65 °C (149 °F; 338 K) (isomer A), 102 °C (isomer B) |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Synthesis
It was first synthesized 1940[2] with the discovery of isomers in 1962.[3] Synthesis involves treating triiron dodecacarbonyl with dimethyl disulfide:
- 2 Fe3(CO)12 + 3 (CH3)2S2 → 3 [Fe(CO)3SCH3]2 + 6 CO
It can be purified by recrystallization or by sublimation. The isomers can be separated by chromatography.
Structure
The methylthioirontricarbonyl dimer is a butterfly cluster compound, consisting of two iron atoms with distorted square pyramidal coordination geometry. The geometry is octahedral if the Fe-Fe bond is included. Each iron has three terminal carbon monoxide ligands and two bridging methylthiolate ligands. The Fe-Fe distance is 2.537 Å with an average Fe-S bond length of 2.259 Å. The average Fe-S-Fe bond angle is relatively small at 68.33°. Three isomers are possible but only the diequatorial and axial-equatorial isomers are seen. The diaxial isomer is disfavored due to steric hindrance.[4][5] The structurally related compound [Fe(CO)3S]2 has idealized C2v symmetry.