C1‑building blocks derived from CO2 for synthesis of high added‑value chemicals

In a global context of industrial decarbonation and reduction of consumption of fossil resources, methodologies that rely on CO2 as a useful carbon source are appealing for achieving a carbon-neutral chemical industry. As direct CO2 utilization is challenging, converting CO2 to C1-building blocks (CO, formic acid, etc.) enables to readily achieve carbonylation reactions.
We have developed a carbonylation method for the synthesis of cyclic anhydrides from lactones and unsaturated acids, using cobalt catalysis. The involved substrates, particularly acrylic acid, can be biosourced. Anhydrides are useful building blocks for polymer synthesis, and are intermediates en route to interesting chemicals (succinic acid, THF, etc.).
The catalytic system is simpler than previously developed, standard catalysts for this reaction. We have developed a carbon chain extension for amines, via a carbonylation-reduction sequence. The same cobalt catalyst can be used for this set of reactions. Finally, we have developed a cyclising carbonylation method of unsaturated acids towards cyclic anhydrides using palladium catalysis. Formic acid serves as the source of CO motif. This method limits the constraints linked to carbon monoxide utilization, and offers industrially relevant anhydride products.