Haloselective Cross-Coupling via Ni/Photoredox Dual Catalysis.

Area of Science:

• Organic Chemistry
• Catalysis
• Synthetic Methodology

Background:

• Chemoselective functionalization of polyfunctional aryl linchpins is vital for efficient molecular diversification.
• While Csp and Csp nucleophiles are well-studied, Csp group introduction remains challenging, especially with Nickel catalysts.

Purpose of the Study:

• To develop a chemoselective method for introducing Csp groups into aryl compounds.
• To address the methodological gap in Nickel-catalyzed Csp-Csp cross-coupling reactions.

Main Methods:

• A "haloselective" cross-coupling reaction using bromo(iodo)arenes and ammonium alkylbis(catecholato)silicates.
• Nickel/photoredox dual catalysis to selectively activate the carbon-iodine bond over the carbon-bromine bond.
• A base-free strategy compatible with various protic functional groups.

Main Results:

• Successful formation of Csp-Csp bonds selectively at the iodine-bearing carbon of bromo(iodo)arenes.
• High-yielding reaction with broad functional group tolerance.
• Demonstration of sequential Csp-Csp bond formation without intermediate purification.

Conclusions:

• The developed Ni/photoredox dual catalysis offers a powerful and selective method for Csp-Csp bond formation.
• This strategy significantly advances the chemoselective functionalization of aryl linchpins.
• The method provides a streamlined approach for synthesizing complex molecules.