Fluorosulfuric Acid-Antimony(V) Fluoride

Abstract

[23854-38-8] F6HO3SSb (MW 316.83) InChI = 1S/FHO3S.5FH.Sb/c1-5(2,3)4;;;;;;/h(H,2,3,4);5*1H;/q;;;;;;+5/p-5 InChIKey = QNDPUZFBWUBSNH-UHFFFAOYSA-I (a strong conjugate Bronsted–Lewis superacid system1 widely used for the generation of stable carbocations and as catalyst and reagent for alkylation, isomerization, rearrangement, cyclization, oxyfunctionalization, formylation, sulfonation, and fluorosulfonation) Alternate Name: Magic Acid®. Physical Data: HSO3F: mp −89.0 °C; bp 162.7 °C; d 1.743 g cm−3. SbF5: bp 149.5 °C; d 2.993 g cm−3. Solubility: sol SO2ClF, liquid SO2; solubilizes most organic compounds that are potential proton acceptors. Form Supplied in: colorless liquid; commercially available. Preparative Methods: HSO3F–SbF5 is prepared by mixing Fluorosulfuric Acid and Antimony(V) Fluoride at rt under dry nitrogen or argon atmosphere. The commercially available Magic Acid is a 50:50 mol % mixture of the two components. Magic Acid diluted in fluorosulfuric acid to various extents is also available. Commercial Magic Acid generally contains some HF in the form of conjugate acid. Handling, Storage, and Precautions: Magic Acid is highly toxic, moisture sensitive, and corrosive, and should always be handled in a fume hood with proper protection. Glass is attacked by Magic Acid very slowly when moisture is excluded. Therefore, glassware may be used for handling and carrying out reactions involving Magic Acid. Teflon containers are recommended for long-term laboratory storage of Magic Acid.