Phenylglyoxal
From Wikipedia, the free encyclopedia
| Phenylglyoxal | |
|---|---|
| Image:Phenylglyoxal.jpg | |
| General | |
| Systematic name | Phenylglyoxal |
| Other names | 1-phenylethanedione |
| Molecular formula | C8H6O2 |
| SMILES | ? |
| Molar mass | 134.13 g/mol (anhydrous) |
| Appearance | yellow liquid (anhydrous) white crystals (hydrate) |
| CAS number | [1075-06-5] (monohydrate) [1074-12-0] (anhydrous) |
| Properties | |
| Density and phase | ? g/cm3 |
| Solubility in water | forms the hydrate |
| Other solvents | common organic solvents |
| Melting point | 76-79 °C (hydrate) |
| Boiling point | 63–65° (0.5 mm, anhydrous) |
| Hazards | |
| MSDS | External MSDS |
| Main hazards | toxic |
| NFPA 704 | |
| Flash point | ? °C |
| R/S statement | R: 22-36/37/38 S: 22-26-36 |
| RTECS number | KM5775180 |
| Supplementary data page | |
| Structure and properties |
n, εr, etc. |
| Thermodynamic data |
Phase behaviour Solid, liquid |
| Spectral data | UV, IR, NMR, MS |
| Related compounds | |
| Related compounds | benzil glyoxal acetophenone |
| Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references |
|
Phenylglyoxal is the chemical compound with the formula C6H5C(O)C(O)H. It is yellow liquid when anhydrous but readily forms a colorless crystalline hydrate. It has been used as a reagent to modify the amino acid arginine.
[edit] Properties
This aldehyde has interesting behavior that illustrate some properties of aldehydes. The yellow liquid solidifes with time, apparently due to oligomerization. Upon heating, this polymer "cracks" to give back the yellow lquid. Dissolution of phenylglyoxal in water gives crystals of the hydrate, C6H5C(O)CH(OH)2. Again by distillation, the anhydrous material is regenerated.
[edit] Preparation
It can be prepared from methyl benzoate by reaction with KCH2S(O)CH3 to give PhC(O)CH(SCH3)(OH), which is oxidized with copper(II) acetate.[1] Alternatively, it can also be prepared by oxidation of acetophenone with selenium dioxide.[2]
