Remote C-H functionalization using radical translocating arylating groups.

Area of Science:

• Organic Chemistry
• Synthetic Chemistry
• Catalysis

Background:

• Site-selective functionalization of unactivated C(sp3)-H bonds is a significant challenge in chemistry.
• Existing methods often rely on transition metal catalysis and directing groups.
• Radical chemistry provides an alternative strategy for remote C-H functionalization.

Purpose of the Study:

• To develop a novel method for radical translocation arylation at unactivated secondary and tertiary C(sp3)-H bonds in alcohols.
• To establish a straightforward two-step sequence for this transformation.
• To achieve regioselective and stereoselective C-H arylation.

Main Methods:

• A two-step sequence involving ionic alcohol sulfonylation with ortho-iodoaryl sulfonyl chlorides.
• A subsequent radical cascade reaction including radical translocation and arylation.
• Utilizing specially designed reagents for efficient radical generation and migration.

Main Results:

• Successful arylation at remote, unactivated secondary and tertiary C(sp3)-H bonds in various alcohols.
• Moderate to good yields were obtained for the γ-arylated alcohols.
• Excellent regioselectivity and good to excellent stereoselectivity were achieved for secondary C(sp3)-H bonds.

Conclusions:

• The developed radical translocation arylation offers a powerful and complementary approach to existing C-H functionalization methods.
• This method provides a straightforward route to γ-arylated alcohols with high selectivity.
• The findings expand the scope of radical chemistry in selective C-H bond functionalization.