Radical sulfonylation with sulfur dioxide surrogates

Area of Science:

• Organic Chemistry
• Environmental Chemistry
• Materials Science

Background:

• Sulfur dioxide (SO₂) is a toxic atmospheric pollutant from fossil fuel combustion.
• Sulfonyl groups are vital in pharmaceuticals, agrochemicals, and materials.
• Direct synthesis from SO₂ is desirable but challenging due to its toxicity.

Purpose of the Study:

• To review advances in radical-mediated sulfonylation using SO₂ surrogates.
• To highlight efficient and greener synthetic methods for SO₂-containing compounds.
• To provide tools for implementing these reactions in organic synthesis.

Main Methods:

• Radical-mediated SO₂ insertion strategies.
• Photocatalysis, electrochemistry, and transition-metal catalysis.
• Thermal initiation for radical generation.

Main Results:

• Significant progress in radical sulfonylation using SO₂ surrogates since 2014.
• Development of diverse SO₂ surrogates as alternatives to gaseous SO₂.
• Mild reaction conditions achieved for sulfonylation.

Conclusions:

• Radical sulfonylation with SO₂ surrogates is a promising synthetic approach.
• These methods offer atom-efficient and greener routes to valuable SO₂ compounds.
• The review provides essential knowledge for synthetic chemists.