Introducing AFS ([Al(SO₃F)₃]) - a thermally stable, readily available, and catalytically active solid Lewis superacid

Area of Science:

• Inorganic Chemistry
• Materials Science
• Catalysis

Background:

• Conventional Lewis superacids often exhibit poor thermal stability and require complex, multi-step syntheses with expensive precursors.
• These limitations hinder the widespread industrial adoption of Lewis superacids.
• There is a need for accessible, stable, and cost-effective superacid catalysts.

Purpose of the Study:

• To present a straightforward and economical synthesis of high-purity aluminium tris(fluorosulfate) (Al(SO3F)3, AFS).
• To demonstrate the thermal stability and superacidic properties of AFS.
• To showcase the synthetic and catalytic utility of AFS in key chemical transformations.

Main Methods:

• A simple, single-step synthesis using commercially available starting materials.
• Characterization of the synthesized aluminium tris(fluorosulfate) for purity and structure.
• Theoretical calculations and experimental techniques to confirm superacidic properties.
• Evaluation of catalytic activity in bond heterolysis and C-F bond activation reactions.

Main Results:

• Successful, cost-effective synthesis of high-purity aluminium tris(fluorosulfate) (AFS) without the need for work-up.
• Demonstrated high thermal stability and confirmed superacidic nature of AFS through theoretical and experimental analyses.
• Exhibited significant catalytic activity in challenging reactions, including bond heterolysis and C-F bond activation.

Conclusions:

• Aluminium tris(fluorosulfate) (AFS) offers a stable, easily synthesized, and cost-effective alternative to conventional Lewis superacids.
• The demonstrated catalytic performance highlights AFS's potential for large-scale industrial applications.
• This work paves the way for broader utilization of superacids in synthetic chemistry and materials science.