Chemodivergent aminocarbonylation enabled by oxygen vacancy-engineered Pd-doped In₂O₃ nanocatalysts

Area of Science:

• Catalysis
• Materials Science
• Organic Synthesis

Background:

• Amide bonds are vital in pharmaceuticals and natural products.
• Synthesizing aryl amides, including α-ketoamides, often involves mono- (MC) and double-aminocarbonylation (DC).
• Selective control over MC and DC pathways for aryl halides remains a significant synthetic challenge.

Purpose of the Study:

• To develop a novel strategy for inverting selectivity between MC and DC pathways.
• To engineer palladium (Pd)-doped indium(III) oxide nanocatalysts with tunable selectivity.
• To achieve efficient synthesis of diverse amides and α-ketoamides.

Main Methods:

• Fabrication of Pd-doped indium(III) oxide nanocatalysts.
• Introduction of oxygen vacancies (O_v) to modulate Pd's second-beyond coordination spheres (SBCSs).
• Investigating the effect of SBCS modulation on catalytic activity and selectivity.

Main Results:

• A novel strategy to invert selectivity from MC to DC was achieved.
• The engineered nanocatalysts demonstrated excellent activity, selectivity, and reusability.
• Over 130 examples of amides and α-ketoamides were synthesized efficiently.
• SBCS modulation facilitated long-range electron transfer, influencing Pd-O bond strength and promoting DC pathway.

Conclusions:

• Oxygen vacancy engineering in Pd-doped indium(III) oxide nanocatalysts offers precise control over aminocarbonylation selectivity.
• This approach provides a versatile platform for synthesizing valuable amide and α-ketoamide compounds.
• The catalyst's reusability and broad applicability highlight its potential for industrial synthesis.