C-H functionalization reactions enabled by hydrogen atom transfer to carbon-centered radicals

Area of Science:

• Organic Chemistry
• Synthetic Chemistry

Background:

• Selective C-H bond functionalization is a key challenge in organic synthesis.
• Radical-based approaches, particularly hydrogen atom transfer (HAT), are gaining prominence.
• HAT offers mild conditions, broad scope, and functional group tolerance, often complementing transition metal catalysis.

Purpose of the Study:

• To review recent advancements in C-H functionalization reactions.
• To focus on methodologies involving the HAT step with carbon-centered radicals.
• To highlight the utility of these methods for remote C(sp3)-H functionalization.

Main Methods:

• Utilizing hydrogen atom transfer (HAT) processes.
• Employing carbon-centered radicals for C-H activation.
• Leveraging mild generation methods for radical species.

Main Results:

• Development of protocols for remote C(sp3)-H functionalization of various compounds (alcohols, amines, amides).
• Expansion of C-H functionalization scope beyond heteroatom-based HAT.
• Demonstration of complementary reactivity to traditional transition metal catalysis.

Conclusions:

• HAT to carbon-centered radicals is a powerful strategy for C-H functionalization.
• These methods provide mild and versatile routes to functionalize inert C-H bonds.
• The field continues to evolve with new developments in radical generation and HAT protocols.