Trifluoroacetic anhydride was originally prepared by the dehydration of trifluoroacetic acid with phosphorus pentoxide.[2] The dehydration might also be carried out with excess α-halogenated acid chlorides. For example, with dichloroacetyl chloride:[3]
It may be used to introduce the corresponding trifluoroacetyl group, for which it is more convenient than the corresponding acyl chloride, trifluoroacetyl chloride, which is a gas.
It can be used to promote reactions of carboxylic acids, including Friedel-Crafts acylation and acylation of other unsaturated compounds. Other electrophilic aromatic substitution reactions can also be promoted with trifluoroacetic anhydride, including nitration, sulfonation and nitrosylation.[2]
^ abTedder, J. M. (1955). "The Use of Trifluoroacetic Anhydride and Related Compounds in Organic Synthesis". Chem. Rev.55 (5): 787–827. doi:10.1021/cr50005a001.
^ abSweeney, Joseph; Perkins, Gemma; DiMauro, Erin F.; Hodous, Brian L. (2005). "Trifluoroacetic Anhydride". Encyclopedia of Reagents for Organic Synthesis. John Wiley & Sons. doi:10.1002/047084289X.rt237.pub2. ISBN978-0-470-84289-8.
^Omura, Kanji; Sharma, Ashok K.; Swern, Daniel (1976). "Dimethyl Sulfoxide-Trifluoroacetic Anhydride. New Reagent for Oxidation of Alcohols to Carbonyls". J. Org. Chem.41 (6): 957–962. doi:10.1021/jo00868a012.