Directing-Group-Assisted C(sp²)-H Arylsulfonylation from Sulfur Dioxide

Area of Science:

• Organic Chemistry
• Catalysis
• Sulfone Synthesis

Background:

• Alkenyl sulfones are important structural motifs in organic synthesis.
• Developing efficient and stereoselective methods for their preparation remains a key challenge.
• Direct C-H functionalization strategies offer atom-economical pathways.

Purpose of the Study:

• To establish a straightforward and stereoselective synthesis of (Z)-β-alkenyl sulfones.
• To explore the direct C(sp2)-H arylsulfonylation of N-tosyl acrylamides.
• To utilize sulfur dioxide as a cost-effective sulfonyl source.

Main Methods:

• Copper-catalyzed reaction involving N-tosyl acrylamides, 1,4-diazabicyclo[2.2.2]octane-sulfur dioxide, and aryldiazonium tetrafluoroborates.
• Direct C(sp2)-H arylsulfonylation using copper trifluoroacetate as the catalyst.
• Sulfur dioxide serves as the sulfonyl group precursor.

Main Results:

• Successful preparation of (Z)-β-alkenyl sulfones with high yields.
• Excellent regio- and stereoselectivity observed during the reaction.
• Demonstration of a direct arylsulfonylation pathway.

Conclusions:

• A novel and efficient method for synthesizing (Z)-β-alkenyl sulfones has been developed.
• The copper-catalyzed reaction provides a stereoselective route with high yields.
• This methodology offers a valuable tool for accessing complex sulfone structures.