Changing the Mechanism for CO2 Hydrogenation Using Solvent‐Dependent Thermodynamics. (23rd October 2017)

• Record Type: Journal Article
• Authors: Burgess, Samantha A.; Appel, Aaron M.; Linehan, John C.; Wiedner, Eric S.
• Is Part Of: Angewandte Chemie. Volume 129:Number 47(2017)
• Page Start: 15198
• Page End: 15201
• Publication Date: 2017-10-23
• Subjects: Homogene Katalyse -- Hydrierungen -- Hydrizität -- Kohlendioxidfixierung -- Lösungsmitteleffekte; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.201709319
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: A critical scientific challenge for utilization of CO2 is the development of catalyst systems that function in water and use inexpensive and environmentally friendly reagents. We have used thermodynamic insights to predict and demonstrate that the HCo I (dmpe)2 catalyst system, previously described for use in organic solvents, can hydrogenate CO2 to formate in water with bicarbonate as the only added reagent. Replacing tetrahydrofuran as the solvent with water changes the mechanism for catalysis by altering the thermodynamics for hydride transfer to CO2 from a key dihydride intermediate. The need for a strong organic base was eliminated by performing catalysis in water owing to the change in mechanism. These studies demonstrate that the solvent plays a pivotal role in determining the reaction thermodynamics and thereby catalytic mechanism and activity.