Decarboxylative Cross-Coupling Enabled by Fe and Ni Metallaphotoredox Catalysis.

Area of Science:

• Organic Chemistry
• Catalysis
• Synthetic Methodology

Background:

• Decarboxylative cross-coupling is vital for C(sp2)-C(sp3) bond formation.
• Existing methods often rely on precious metals like Iridium.
• Developing base metal alternatives is crucial for sustainable synthesis.

Purpose of the Study:

• To develop a novel base metal-catalyzed decarboxylative cross-coupling reaction.
• To utilize an iron-nickel catalytic system for enhanced reactivity and selectivity.
• To explore the scope and limitations of this new synthetic transformation.

Main Methods:

• Employing an iron(III) chloride (FeCl3) cocatalyst.
• Utilizing a pyridine carboxamidine nickel catalyst.
• Investigating the coupling of various aryl iodides with carboxylic acids under light irradiation.

Main Results:

• High yields achieved in the coupling of aryl iodides with carboxylic acids, outperforming other halides.
• Successful coupling of diverse carboxylic acid derivatives, including heterocycles and amino acids.
• Demonstrated preferential coupling of carboxylic acids over boronic acid esters and triflates.

Conclusions:

• The developed Fe/Ni system provides a robust and selective method for decarboxylative cross-coupling.
• The catalytic system offers a cost-effective and efficient approach to C(sp2)-C(sp3) bond formation.
• Proposed mechanism involves iron-catalyzed carboxylic acid activation and nickel-mediated aryl iodide coupling.