Lewis Acid-Catalyzed Sulfur Fluoride Exchange

Area of Science:

• Organic Chemistry
• Catalysis
• Materials Science

Background:

• Sulfur fluoride exchange (SuFEx) click chemistry is a powerful tool for molecular construction.
• Existing SuFEx methods often require harsh conditions or specific reagents, limiting their scope.
• Developing milder and more versatile catalytic systems for SuFEx is highly desirable.

Purpose of the Study:

• To introduce a novel catalytic system for SuFEx reactions using metal Lewis acids.
• To demonstrate the broad applicability of this method for synthesizing diverse S-N bond-containing compounds.
• To explore the efficacy of different metal Lewis acids in catalyzing sulfur fluoride exchange.

Main Methods:

• Utilized metal Lewis acids, including Ca(NTf2)2, as catalysts for the conversion of sulfonyl fluorides, fluorosulfates, and sulfamoyl fluorides.
• Employed silyl amines as coupling partners in the sulfur fluoride exchange reaction.
• Investigated both in situ-generated and commercially available silyl amines.

Main Results:

• Successfully synthesized sulfonamides, sulfamates, and sulfamides with yields ranging from 35-99%.
• Ca(NTf2)2 demonstrated high catalytic activity and selectivity.
• Other metal Lewis acids also effectively catalyzed SuFEx reactions, yielding comparable results for sulfonamides and sulfamates.

Conclusions:

• Metal Lewis acid-catalyzed sulfur fluoride exchange offers a robust and efficient pathway to S-N compounds.
• The developed method provides a versatile approach for accessing important chemical scaffolds.
• This catalytic system expands the toolkit for SuFEx click chemistry applications.