出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2014/11/29 21:42:56」(JST)
| Trifluoroacetic acid | |||
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IUPAC name
2,2,2-Trifluoroethanoic acid |
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Other names
Perfluoroacetic acid |
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| Identifiers | |||
| CAS number | 76-05-1 Y | ||
| PubChem | 6422 | ||
| ChemSpider | 10239201 Y | ||
| UNII | E5R8Z4G708 Y | ||
| ChEBI | CHEBI:45892 N | ||
| ChEMBL | CHEMBL506259 Y | ||
| RTECS number | AJ9625000 | ||
| Jmol-3D images | Image 1 | ||
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SMILES
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InChI
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| Properties | |||
| Molecular formula | C2HF3O2 | ||
| Molar mass | 114.02 g/mol | ||
| Appearance | colorless liquid | ||
| Density | 1.489 g/cm3, 20 °C | ||
| Melting point | −15.4 °C (4.3 °F; 257.8 K) | ||
| Boiling point | 72.4 °C (162.3 °F; 345.5 K) | ||
| Solubility in water | miscible | ||
| Acidity (pKa) | 0.23 [1] | ||
| Hazards | |||
| MSDS | External MSDS | ||
| R-phrases | R20 R35 R52/53 | ||
| S-phrases | S9 S26 S27 S28 S45 S61 | ||
| Main hazards | Highly corrosive | ||
| NFPA 704 |
1
3
1
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| Flash point | −3 °C (27 °F; 270 K) | ||
| Related compounds | |||
| Related perfluorinated acids | Perfluorooctanoic acid Perfluorononanoic acid |
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| Related compounds | Acetic acid Trichloroacetic acid |
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| Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa) | |||
| N (verify) (what is: Y/N?) | |||
| Infobox references | |||
Trifluoroacetic acid (TFA) is the organofluorine compound with the chemical formula CF3CO2H. It is a colourless liquid with a sharp odor, similar to vinegar, but stronger. It is a ~34,000-fold stronger acid than acetic acid due to the influence of the electronegative trifluoromethyl group. TFA is widely used in organic chemistry.
TFA is prepared industrially by the electrofluorination of acetyl chloride and acetic anhydride, followed by hydrolysis of the resulting trifluoroacetyl fluoride:[2]
Where desired, this compound may be dried by addition of trifluoroacetic anhydride.[3]
An older route to TFA proceeds via the oxidation of 1,1,1-trifluoro-2,3,3-trichloropropene with potassium permanganate. The trifluorotrichloropropene can be prepared by Swarts fluorination of hexachloropropene.
TFA occurs naturally in sea water, but only in small concentrations (<200 ng/L).[4][5]
TFA is the precursor to many other fluorinated compounds such as trifluoroacetic anhydride and 2,2,2-trifluoroethanol.[2] It is a reagent used in organic synthesis because of a combination of convenient properties: volatility, solubility in organic solvents, and its strength as an acid.[6] TFA is also less oxidizing than sulfuric acid but more readily available in anhydrous form than many other acids. One complication to its use is that TFA forms an azeotrope with water (b. p. 105 °C).
TFA is popularly used as a strong acid in peptide synthesis and other organic synthesis to remove the t-butoxycarbonyl protecting group.[7][8]
At a low concentration, TFA is used as an ion pairing agent in liquid chromatography (HPLC) of organic compounds, particularly peptides and small proteins. TFA is a versatile solvent for NMR spectroscopy (for materials stable in acid). It is also used as a calibrant in mass spectrometry.[9]
TFA is used to produce trifluoroacetate salts.[10]
Trifluoroacetic acid is a corrosive acid but it does not pose the hazards associated with hydrofluoric acid because the carbon-fluorine bond is not labile. Toxic. Irreversible inhibitor of acetylcholinesterase enzyme.[citation needed]
| リンク元 | 「TFA」「トリフルオロ酢酸塩」「トリフルオロ酢酸」「trifluoroacetic acid」 |