Thioarylative Radical Cyclization of Yne-Dienone.

Area of Science:

• Organic Chemistry
• Synthetic Chemistry
• Medicinal Chemistry

Background:

• Dihydrochromenones are important scaffolds in medicinal chemistry.
• Efficient synthesis of functionalized dihydrochromenones remains a challenge.
• Radical cyclization offers a powerful strategy for ring construction.

Purpose of the Study:

• To develop a novel chemo- and regioselective method for synthesizing 3-thioaryl dihydrochromenones.
• To explore the utility of N-hydroxyphthalimide (NHPI) in radical cyclization reactions.
• To demonstrate the synthetic versatility of the newly synthesized compounds.

Main Methods:

• N-hydroxyphthalimide (NHPI)-mediated radical cyclization.
• Reaction of yne-dienones with thiols.
• TEMPO quenching experiments to confirm radical intermediates.

Main Results:

• Successful construction of 3-thioaryl bearing [6,6]-fused dihydrochromenone derivatives.
• The reaction exhibits broad substrate scope and functional group tolerance.
• Thioaryl radical addition to the alkyne was identified as the key step.

Conclusions:

• A new NHPI-mediated radical cyclization provides efficient access to valuable dihydrochromenone derivatives.
• The developed method is chemo- and regioselective, offering synthetic advantages.
• The synthesized compounds show potential for further functionalization and application in drug discovery.