Magic acid is a strong conjugate Br?nsted-Lewis superacid system widely used for the generation of stable carbocations and as catalyst and reagent for alkylation, isomerization, rearrangement, cyclization, oxyfunctionalization, formylation, sulfonation, and fluorosulfonation.
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.
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.