Trifluoroacetic Acid Cf3Cooh

a colorless, fuming liquid that can burn the skin severely and has a sharp, irritating odor. Melting point, –15.4°C; boiling point, 72.4°C; density, 1.489 g/cm³ at 20°C. It is miscible with water and most organic solvents, and it forms stable complexes with water, ether, and acetone.

Trifluoroacetic acid is a very strong acid, with dissociation constant K₂₅ = 0.588. It separates free acids from the salts of carbox-ylic acids, hydrochloric acid, and nitric acid, and it decomposes metals and rubber. However, it is inert to fluoroplastics and dry glass. It forms derivatives characteristic of carboxylic acids, the most important of which is the anhydride (CF₃CO)₂O. Trifluoroacetic anhydride, like trifluoroacetic acid itself, is used in the production of cellulose acetate. Trifluoroacetic acid is also used as a solvent in organic syntheses and for the introduction of the easily removed CF₃CO protective group (in the chemical transformations of carbohydrates and the hydrolysis of peptides). Peroxytrifluoroacetic acid, CF3COOOH, which is obtained by mixing trifluoroacetic acid with hydrogen peroxide, is an efficient oxidizing agent.

Trifluoroacetic acid is produced mainly by the electrochemical fluorination of acetic anhydride in anhydrous hydrogen fluoride.