User:Rifleman 82/Benzophenone
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| Benzophenone | |
|---|---|
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| General | |
| Systematic name | Benzophenone |
| Other names | diphenylmethanone phenyl ketone diphenyl ketone benzoylbenzene |
| Molecular formula | C13H10O |
| SMILES | O=C(C2=CC=CC=C2) C1=CC=CC=C1 |
| Molar mass | 182.217 g/mol |
| Appearance | white solid |
| CAS number | [119-61-9] |
| Properties | |
| Density and phase | 1.11 g/cm3, solid |
| Solubility in water | insoluble |
| Other solvents | benzene, THF, ethanol, propylene glycol |
| Melting point | 47.9 °C |
| Boiling point | 305.4 °C |
| Dipole moment | |
| Hazards | |
| MSDS | External MSDS |
| Main hazards | flammable |
| NFPA 704 | |
| Flash point | ? °C |
| R/S statement | R: ? S: ? |
| RTECS number | ? |
| Supplementary data page | |
| Structure and properties |
n, εr, etc. |
| Thermodynamic data |
Phase behaviour Solid, liquid, gas |
| Spectral data | UV, IR, NMR, MS |
| Related compounds | |
| Related compounds | benzil, acetophenone |
| Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references |
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Benzophenone is the organic compound with the formula (C6H5)2CO, generally abbreviated Ph2CO. Substituted benzophenones such as oxybenzone and dioxybenzone are used in sunscreen.
Contents |
[edit] Synthesis and reactions
Benzophenone can be prepared by the reaction of benzene with carbon tetrachloride followed by hydrolysis of the resulting diphenyldichloromethane.[1]
Benzophenone is commonly used as a photosensitizers in photochemistry. Its triplet is readily quenched by oxygen, and can also react with a suitable hydrogen donor to for a ketyl radical.
[edit] Benzyophenone ketyl radical
Sodium is commonly used as a desiccant to purify solvents by reacting with water to give the hydroxide, which is nonvolatile:
- Na + H2O → NaOH + 1/2 H2
Themain problem with the use of Na as a desiccant (below its meltingpoint) is associated with the slow rate of reaction between a solidsand a solution. When however, the desiccant is soluble, the speed ofdrying is much higher. Benzophenone is often used to generate such asoluble drying agent,. An advantage to this application is the intensebluecolor of the ketyl radical anion. Thus, benzophenone/Na can be used asan indicator of air-free and moisture-free conditions in thepurification of solvents by distillation.
[edit] Derivatives
- p,p'-bis(N,N-dimethylamino)benzophenone or Michler's ketone has dimethylamino substituents at each para position.
[edit] See also
[edit] References
- ^ Marvel, C. S.; Sperry, W. M., "Benzophenone". Organic Syntheses, Collected Volume 1, p. 95 (1941).
[edit] External links
[edit] References
- Merck Index, 11th Edition, 1108.
- Anion Radicals
[edit] Gallery
 A bottle of benzophenone by Lancaster. |
 Toluene is refluxed with sodium and benzophenone to produce dry, oxygen-free toluene. |
 The mixture is still not blue yet indicating that the reaction is not complete. |
 The intense blue coloration due to the benzophenone ketyl radical shows that the toluene is considered free of air and moisture. |
 After the toluene has beenthoroughly dried by the sodium and benzophenone, it is distilled atatmospheric pressure under a slight positive pressure of nitrogen toprevent contamination by air into the receiving Schlenk flask. |
