三氟乙酸，Trifluoroacetic acid [TFA]；ReagentPlus®, 99%

Trifluoroacetic acid (TFA) is an organofluorine compound used as a reagent in organic synthesis for various acid-catalyzed reactions such as ring-opening of epoxides, biomimetic cyclization, Cope rearrangements, and natural product synthesis. TFA′s physicochemical characteristics provide advantages over other acids because of its high volatility, solubility in organic solvents, and acidic strength. When TFA is used as a reagent the product isolation is simple by evaporation due to its very high volatility. Less volatile acids such as sulfuric acid or p-toluenesulfonic acid may require neutralization or an extractive workup.[1]

 

Trifluoroacetic acid can be used as a reagent:      

• For the cleavage of nitrogen and oxygen protecting groups such as N-Boc, N-benzyloxymethyl, benzyl ether, p-methoxybenzyl ether, t-butyl ether, t-butyloxymethyl ether, triphenylmethyl ether, and dimethyl acetals.[1][2][3]      
• In the Baeyer–Villiger oxidation reactions in combination with sodium percarbonate.[1],·      
• For the C-H trifluoromethylation of arenes.[4]

TFA can also be used as:      

• A solvent in atom transfer cyclization reactions and polymer processes.[2]      
• A catalyst in the synthesis of ε-caprolactam via Beckmann rearrangement of cyclohexanone oxime in aprotic solvents.[5]

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