Unlocking Multi-Product Selectivity in Olefin Electro-oxidation through Cooperative Cation/Oxygen Species Modulation

Area of Science:

• Green Chemistry
• Electrochemical Synthesis
• Catalysis

Background:

• Selective olefin oxidation is crucial for producing valuable oxygen-containing compounds.
• Traditional methods often require harsh stoichiometric oxidants.
• Electrochemical oxidation offers a cleaner alternative but lacks control over product selectivity.

Purpose of the Study:

• To develop a tunable electrochemical strategy for selective olefin oxidation.
• To achieve high yields of vicinal diols, aldehydes, and epoxides.
• To elucidate the mechanistic roles of oxygen species and cations.

Main Methods:

• Electrochemical oxidation of olefins using dimensionally stable anodes (DSAs).
• Systematic tuning of cations (Li+, tetraethylammonium, tetrabutylammonium) to control reaction pathways.
• Mechanistic studies to understand intermediate stabilization and reaction steering.

Main Results:

• Achieved >90% selectivity for vicinal diols, aldehydes, and epoxides.
• Demonstrated Li+ ions stabilize *OH for diol formation.
• Showcased tetraethylammonium cations promoting C=C cleavage for aldehydes.
• Revealed tetrabutylammonium cations facilitating O2 reduction for epoxide synthesis.

Conclusions:

• Developed a versatile electrochemical olefin oxidation strategy via oxygen species and cation co-tuning.
• Provides a green and efficient alternative to stoichiometric oxidants.
• Highlights the potential of cation tuning for precise control in electro-organic synthesis.