Liberation of acrylates from nickelalactones via Ni─O ring opening with alkyl iodides

The utilization of carbon dioxide as a feedstock for the production of raw chemicals is of high current industrial interest. One attractive reaction is the transformation of carbon dioxide into acrylic acid or acrylates. The cleavage of the Ni─O bond of nickelalactones may result in the formation of acrylates. In this work, C₂H₅I, CF₃CH₂I and CF₃I are studied as alkylation reagents for the Ni─O ring opening of nickelalactones. The results indicate that both C₂H₅I and CF₃CH₂I are able to release acrylates from nickelalactones. Based on the experimental evidence and literature precedents, a mechanism – proceeding via Ni─O ring opening of nickelalactone, β-H elimination to release the acrylate and reductive elimination for recovery of the Ni(0) species – is proposed.