Description
Trifluoromethanesulfonic acid, also known as triflic acid, TFMS, TFSA, HOTf or TfOH, is a sulfonic acid with the chemical formula CF3SO3H. It is often regarded as one of the strongest acids, and is one of a number of so-called "superacids". it is used in the manufacture of pharmaceuticals, agricultural chemicals and polymers. The anhydrous form is widely used in fine chemical synthesis. It is non-oxidizing, has a high thermal stability, and is resistance to both oxidation and reduction, which makes it one of the more useful compounds in the super acids class. In the pharma industry, it is used to make a number of drug classes, including nucleosides, antibiotics, steroids, proteins and glycosides. Triflic anhydride reacts readily with water and has an unfavorable toxicity profile.
Chemical Properties
Trifluoromethanesulfonic acid is a hygroscopic, colorless liquid at room temperature. It is soluble in polar solvents such as dimethylformamide (DMF), dimethyl sulfoxide (DMSO), acetonitrile, and dimethyl sulfone. Addition of triflic acid to polar solvents can be dangerously exothermic.
Trifluoromethanesulfonic acid is widely used especially as a catalyst and a precursor in organic chemistry. With an Ka = 8. 0 1014 (pKa ~ -15) mol/kg, HOTf qualifies as a superacid. Triflic acid owes many of its useful properties to its great thermal and chemical stability. Both the acid and its conjugate base CF3SO3-, known as triflate, resist oxidation/reduction reactions, whereas many strong acids are oxidizing, e. g. HClO4 and HNO3. The triflate anion is immune to attack by even strong nucleophiles. Because of its resistance to oxidation and reduction, triflic acid is a very useful and versatile reagent. Further recommending its use, triflic acid does not sulfonate substrates, which can be a problem with sulfuric acid, fluorosulfuric acid, and chlorosulfonic acid. Below is a prototypical sulfonation, which HOTf does not undergo: C6H6 + H2SO4 → C6H5(SO3H) + H2O.
Preparation
Yellow-brown liquid. The boiling point is 167~170 ℃.The refractive index is 1.331.The relative density is 1.708.It is the strongest organic acids, easily soluble in water.Use carbon disulfide as raw material, with the reaction of iodine pentafluoride to produce trifluoromethyl disulfide.(CF3S) 2Hg was obtained when reacting with mercury; Then through oxidation of hydrogen oxide, trifluoromethanesulfonic acid is acquired.
Uses
- It is used for organic synthesis, widely used in pharmaceutical and chemical industries, such as nucleosides, antibiotics, steroids, protein, sugar, vitamins synthesis, silicone rubber modification.
- Isomerization and alkylation of the catalyst, the preparation of 2, 3-dihydro-2-indanone, tetralone, glycosides in the removal of glycoproteins.
Reactions
Trifluoromethanesulfonic acid acts as a catalyst for esterification reactions and an acidic titrant in nonaqueous acid-base titration. It is useful in protonations due to the presence of conjugate base triflate is non nucleophilic. It serves as a deglycosylation agent for glycoproteins. In addition, it is a precursor and a catalyst in organic chemistry. It reacts with acyl halides to prepare mixed triflate anhydrides, which are strong acylating agents used in Friedel-Crafts reactions. It acts as a key starting material for the preparation of ethers and olefins by reacting with alcohols as well as to prepare trifluoromethanesulfonic anhydride by dehydration reaction.
Catalyst used in the production of cocoa butter substitute from palm oil. This is a very similar reaction to what would be done if one wanted to create polymers using triflic acid in the synthesis. Other Friedel-Crafts type reactions using triflic acid include cracking of alkanes and alkylation of alkenes which are very important to the petroleum industry. These triflic acid derivative catalysts are very effective in isomerizing straight chain or slightly branched hydrocarbons that can increase the octane rating of a particular petroleum based fuel.
Uses
Trifluoromethanesulfonic acid acts as a catalyst in Friedel-Crafts type acylation, alkylation and polymerization reactions; as a solvent for ESR; as a nonaqueous strong acid titrant; with trifluoroacetic acid, q.v., in solid-phase peptide synthesis. One of the strongest available monoprotic acids.
Definition
ChEBI: Trifluoromethanesulfonic acid is a one-carbon compound that is methanesulfonic acid in which the hydrogens attached to the methyl carbon have been replaced by fluorines. It is a one-carbon compound and a perfluoroalkanesulfonic acid. It is a conjugate acid of a triflate.
General Description
Trifluoromethanesulfonic acid is a strong organic acid. It can be prepared by reacting bis(trifluoromethylthio)mercury with H
2O
2. On mixing with HNO
3, it affords a nitrating reagent (a nitronium salt). This reagent is useful for the nitration of aromatic compounds. Its dissociation in various organic solvents has been studied.
Safety Profile
A corrosive irritant to
the skin, eyes, and mucous membranes. A
strong acid. Violent reaction with acyl
chlorides or aromatic hydrocarbons evolves
toxic hydrogen chloride gas. When heated to
decomposition it emits toxic fumes of Fand
SOx. See also FLUORIDES.
