Inverting polarity in a cobalt MHAT reaction via reductive catalytic turnover.

Area of Science:

• Organic Chemistry
• Catalysis
• Radical Chemistry

Background:

• Metal hydride hydrogen-atom-transfer (MHAT) catalysis is vital for selective hydrogen atom transfer to olefins in organic synthesis.
• Current MHAT catalysis primarily follows an oxidative pathway, forming electrophilic alkyl-metal intermediates.
• Reversing olefin polarity for nucleophilic internal carbon atoms via MHAT remains an underexplored area.

Purpose of the Study:

• To develop a reductive MHAT cycle for radical-polar-crossover reactions.
• To enable hydrofunctionalization of olefins with electrophiles by inverting their inherent polarity.
• To establish a novel synthetic platform for organic synthesis.

Main Methods:

• Development of a reductive metal hydride hydrogen-atom-transfer (MHAT) catalytic cycle.
• Integration of reductive radical-polar-crossover with MHAT catalysis.
• Application to Markovnikov-selective hydrocarboxylation using carbon dioxide.

Main Results:

• Demonstrated a reductive MHAT cycle merging radical chemistry with polar transformations.
• Achieved inverted olefin polarity, enabling hydrofunctionalization with electrophiles.
• Successfully applied the method for Markovnikov-selective hydrocarboxylation using atmospheric CO2.

Conclusions:

• The developed reductive MHAT cycle offers a novel approach for organic synthesis by inverting olefin polarity.
• This method provides a mild pathway for hydrocarboxylation and can be used for synthesizing and functionalizing drug-like molecules.
• The mechanistic pathway differs from other metal-catalyzed reactions, offering unique synthetic advantages.