Deep-Red to Near-Infrared Light-Driven Radical Generation from Organoboron Compounds via Ligand-Induced Direct...

Area of Science:

• Organic Chemistry
• Photochemistry
• Catalysis

Background:

• Carbon-centered radicals are crucial intermediates in organic synthesis.
• Generating radicals often requires harsh conditions or specific precursors.
• Developing mild and efficient radical generation methods is highly desirable.

Purpose of the Study:

• To develop a novel catalytic strategy for generating carbon-centered radicals.
• To utilize deep-red to near-infrared (DR to NIR) light for photochemical activation.
• To enable diverse organic transformations using organoboron compounds.

Main Methods:

• Employing aza-dipyrromethene (ADP) catalysts for photoactivation.
• Utilizing DR to NIR light irradiation for direct excitation of substrate-catalyst complexes.
• Investigating the formation of photoactive borate intermediates and C-B bond cleavage.

Main Results:

• Demonstrated a catalytic strategy for generating carbon radicals from organoboron compounds.
• Showcased ligand-induced photochemical activation via borate intermediates.
• Confirmed the role of direct excitation through mechanistic studies.
• Achieved diverse transformations including Giese addition, C-heteroatom bond formation, radical-radical coupling, and Ni-catalyzed cross-coupling.

Conclusions:

• The developed method provides a versatile and efficient route for carbon radical generation under mild photoredox conditions.
• This approach broadens the scope of organoboron compounds in radical chemistry.
• The strategy offers a powerful tool for constructing complex molecules.