Base Metal Catalyst for Indirect Hydrogenation of CO2

We herein reporta novel Mn-SNS-based catalyst, which is capableof performing indirect hydrogenation of CO2 to methanol via formylation. In this domain of CO2 hydrogenation,pincer ligands have shown a clear predominance. Our catalyst is basedon the SNS-type tridentate ligand, which is quite stable and cheapas compared to the pincer type ligands. The catalyst can also be recycledeffectively after the formylation reaction without any significantchange in efficiency. Various amines including both primary and secondaryamines worked well under the protocol to provide the desired formylatedproduct in good yields. The formed formylated amines can also be reducedfurther at higher pressures of hydrogen. As a whole, we have developeda protocol that involves indirect CO2 hydrogenation tomethanol that proceeds via formylation of amines.

Automated summary

We have developed a novel Mn-SNS-based catalyst for the indirect hydrogenation of CO2 to methanol via formylation. Our catalyst, based on the stable and inexpensive SNS-type tridentate ligand, showed excellent recyclability and effectiveness in the formylation reaction. Various amines, including primary and secondary amines, worked well under the protocol to provide the desired formylated product in good yields. The formed formylated amines can also be further reduced at higher pressures of hydrogen.