Intermolecular Radical C-H Bond Activation: A Powerful Tool for Late Stage Functionalization

Area of Science:

• Organic Chemistry
• Synthetic Chemistry

Background:

• Radical reactions are crucial for synthesizing complex molecules, forming C-C and C-heteroatom bonds.
• Tin-based reagents have historically dominated radical chemistry, enabling unique transformations and providing kinetic data.
• However, tin reagents and byproducts pose toxicity and purification challenges, driving interest in tin-free alternatives.

Purpose of the Study:

• To review alternative, tin-free methods for radical reactions.
• To highlight the use of C-H bonds as radical precursors via intermolecular hydrogen atom transfer (HAT).
• To showcase advancements in C-C and C-heteroatom bond formation using C-H activation.

Main Methods:

• Focuses on intermolecular hydrogen atom transfer (HAT) for radical generation.
• Utilizes C-H bonds as a more sustainable alternative to alkyl halides.
• Reviews early and recent developments in C-H activation for radical synthesis.

Main Results:

• Demonstrates the successful application of C-H activation in radical reactions.
• Provides examples of both C-C and C-heteroatom bond formations.
• Highlights the progress in developing tin-free radical methodologies.

Conclusions:

• Tin-free radical chemistry using C-H activation is a viable and developing field.
• These methods offer a greener and potentially simpler alternative to traditional tin-mediated synthesis.
• Further research in C-H activation promises new synthetic strategies for complex molecules.