Pentaphenylantimony
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| Names | |
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| Preferred IUPAC name
Pentaphenyl-λ5-stibane | |
| Identifiers | |
3D model (
JSmol ) |
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| ChemSpider | |
PubChem CID
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CompTox Dashboard (EPA)
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| Properties | |
| C30H25Sb | |
| Molar mass | 507.290 g·mol−1 |
| Related compounds | |
Other cations
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Related compounds
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Pentamethylantimony Pentaethylantimony |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Pentaphenylantimony is an
organoantimony compound containing five phenyl groups attached to one antimony
atom. It has formula Sb(C6H5)5 (or SbPh5).
Properties
The solid is colourless and melts at 169-170°C.[1]
As a solid the pure form crystallises with a roughly square pyramidal shape. It can also form
trigonal bipyramid shape.[2] When dissolved, molecules are also trigonal bipyramidal.[2] However with nuclear magnetic resonance, in solution, the phenyl groups all appear to be equivalent. This is probably because the molecule is not stable in shape and orientation of phenyl changes rapidly.[3]
Solid pure pentaphenylantimony forms
triclinic crystals in the P1 space group. The unit cell has a=10.286 b=10.600 and c=13.594 Å, α=79.20° β=70.43° γ=119.52°. The basal Sb-C bond length is 2.216 Å whereas the apex Sb-C length is 2.115 Å.[1]
Reactions
Pentaphenylantimony reacts with a variety of reagents that replace one or more phenyl groups with a different substituent. Reagents with acidic hydrogen give
synthons
of them) give the analogous halobenzene as byproduct:
- Ph5Sb + HOR → PhH + Ph4SbOR
- Ph5Sb + HX → PhH + Ph4SbX
- Ph5Sb + X2 → PhX + Ph4SbX
For example, pentaphenylantimony reacts with dicarboxylic acids in solution, by substituting a phenyl group with the acid hydrogen. This yields a tetraphenyl antimony or bis(tetraphenyl antimony) compound.[4][5][6][7]
When heated, pentaphenylantimony forms
p-quaterphenyl.[8]
Pentaphenylantimony reacts with bromine to make
phenyl radical.[8]
Formation
Pentaphenylantimony can be formed by reacting dichlorotriphenylantimony with
phenyl lithium.[1]
References
Further reading
- Smirnova, N.N.; Letyanina, I.A.; Larina, V.N.; Markin, A.V.; Sharutin, V.V.; Senchurin, V.S. (January 2009). "Thermodynamic properties of pentaphenylantimony Ph5Sb over the range from T→0K to 400K". The Journal of Chemical Thermodynamics. 41 (1): 46–50. .
- Brock, C. P.; Ibers, J. A. (1976-01-01). "The role of crystal packing forces in the structure of pentaphenylantimony". Acta Crystallographica Section A. 32 (1): 38–42. .