Trifluoroacetic acid 3019112 225098705 2008-07-11T21:37:21Z 69.255.156.153 {{Chembox new | Name = Trifluoroacetic acid | ImageFileL1 = Trifluoroacetic-acid-skeletal.png | ImageSizeL1 = 100px | ImageFileR1 = Trifluoroacetic-acid-3D-vdW.png | ImageSizeR1 = 120px | ImageFile2 = Trifluoroacetic-acid-elpot.png | ImageSize2 = 120px | IUPACName = 1,1,1-Trifluoroethanoic acid | OtherNames = Perfluoroacetic acid<br />Trifluoroethanoic acid<br />TFA | Section1 = {{Chembox Identifiers | SMILES = FC(F)(F)C(O)=O | CASNo = 76-05-1 | RTECS = AJ9625000 }} | Section2 = {{Chembox Properties | Formula = C<sub>2</sub>HF<sub>3</sub>O<sub>2</sub> | MolarMass = 114.03 g/mol | Appearance = colorless liquid | Density = 1.5351 g/cm<sup>3</sup>, 20 °C | Solubility = miscible | MeltingPt = -15.4 °C; 257.75 K | BoilingPt = 72.4 °C; 345.55 K | pKa = 0.3 | Viscosity = }} | Section7 = {{Chembox Hazards | ExternalMSDS = [http://www.jtbaker.com/msds/englishhtml/t5525.htm External MSDS] | MainHazards = Highly corrosive | NFPA-H = 3 | NFPA-R = 1 | NFPA-F = 1 | FlashPt = -3 °C | RPhrases = {{R20}} {{R35}} {{R52/53}} | SPhrases = {{S9}} {{S26}} {{S27}} {{S28}} {{S45}} {{S61}} }} | Section8 = {{Chembox Related | OtherCpds = [[Acetic acid]]<br />[[Trichloroacetic acid]] }} }} '''Trifluoroacetic acid''' (TFA) is the [[chemical compound]] with the formula CF<sub>3</sub>CO<sub>2</sub>H. It is a strong [[carboxylic acid]] due to the influence of the three very [[electronegativity|electronegative]] [[fluorine]] atoms. Relative to [[acetic acid]], TFA is almost 100,000-fold more acidic. TFA is widely used in [[organic chemistry]]. ==Uses== TFA is a [[reagent]] used frequently in [[organic synthesis]] because of a combination of convenient properties: volatility, solubility in organic solvents, and its strength.<ref>Eidman, K. F.; Nichols, P. J. "Trifluoroacetic Acid" in Encyclopedia of Reagents for Organic Synthesis (Ed: L. Paquette) 2004, J. Wiley & Sons, New York. {{doi|10.1002/047084289}}</ref> It is also less oxidizing than [[sulfuric acid]] but more readily available in anhydrous form than [[hydrochloric acid]]. One complication to its use is that TFA forms an [[azeotrope]] with water with a boiling point of 105 °C. It is also frequently used as a buffer in liquid chromatography for separation of organic compounds, particularly peptides and small proteins. It is a versatile solvent for [[NMR spectroscopy]] (for materials stable in acid). The derived [[acid anhydride]], [CF<sub>3</sub>C(O)]<sub>2</sub>O, is a common reagent for introducing the trifluoracetyl group. ==Synthesis== Electrofluorination of [[acetic acid]] with the [[Simons method]] is the best way to obtain trifluoroacetic acid. The [[anodic]] reaction of the [[electrolysis]] of a mixture of [[hydrogen fluoride]] and acetic acid below the voltage at which [[chemical element|elemental]] [[fluorine]] (F<sub>2</sub>) develops is a mild reaction which leaves the [[carboxylic group]] intact. ==References== {{reflist}} [[Category:Carboxylic acids]] [[Category:Organofluorides]] [[cs:Kyselina trifluoroctová]] [[de:Trifluoressigsäure]] [[fr:Acide trifluoroacétique]] [[it:Acido trifluoroacetico]] [[nl:Trifluorazijnzuur]] [[ja:トリフルオロ酢酸]] [[pl:Kwas trifluorooctowy]]