Radical Sulfimidation via Visible-Light Photoredox Catalysis: N-Acyloxyamides as Bench-Stable Nitrene Surrogates

Area of Science:

• Organic Chemistry
• Catalysis
• Synthetic Methodology

Background:

• Sulfimidation of thioethers is crucial for synthesizing sulfur-containing compounds.
• Developing efficient and mild catalytic methods for sulfimidation remains an active research area.

Purpose of the Study:

• To develop a novel visible-light-driven protocol for the sulfimidation of thioethers.
• To utilize N-acyloxyamides as effective sulfimidating agents.
• To explore the catalytic activity of TPT in this transformation.

Main Methods:

• Visible-light irradiation was employed to drive the reaction.
• The reaction utilized N-acyloxyamides as the source of the imido group.
• TPT (4-Trifluoromethylphenyl)iodonium(III) triflate) served as the catalyst.
• The reaction was performed under ambient conditions, tolerating various functional groups.

Main Results:

• The protocol achieved high yields (up to 99%) for the desired sulfimidation products.
• The reaction demonstrated broad functional group tolerance.
• Gram-scale synthesis was successful with only 1 mol % catalyst loading.
• Diverse products, including N-allyl-N-(thio)amides, N-sulfonyl sulfimides, and N-acyl sulfoximines, were obtained.

Conclusions:

• A novel, efficient, and mild visible-light-driven sulfimidation of thioethers has been established.
• The methodology offers a versatile route to various valuable sulfur-containing compounds.
• Preliminary mechanistic studies suggest a radical cross-coupling pathway.