Highly Selective Carbonylation of Olefins Using CO₂ and H₂

Area of Science:

• Catalysis
• Organometallic Chemistry
• Green Chemistry

Background:

• Direct carbonylation of olefins with CO2 remains a significant challenge in synthetic chemistry.
• Developing efficient catalytic systems for CO2 utilization is crucial for sustainable chemical processes.

Purpose of the Study:

• To develop a novel multimetallic catalyst system for the direct carbonylation of olefins using carbon dioxide and hydrogen.
• To achieve selective formation of aliphatic esters with high regioselectivity.

Main Methods:

• Utilized a catalyst system comprising palladium and iridium precursors with specific phosphine ligands (e.g., 1,2-bis(di-tert-butylphosphinomethyl)benzene).
• Employed zinc triflate (Zn(OTf)2) as an acidic additive.
• Conducted detailed control experiments and mechanistic investigations.

Main Results:

• Achieved direct carbonylation of aliphatic and aromatic olefins with CO2 and hydrogen.
• Demonstrated selective formation of aliphatic esters with unparalleled regioselectivity.
• Proposed a catalytic cycle involving initial Ir-catalyzed formate formation followed by Pd-catalyzed alkoxycarbonylation.

Conclusions:

• The developed multimetallic catalyst system offers an efficient route for CO2 utilization in ester synthesis.
• The system shows promise for industrial applications due to its effectiveness with industrially relevant alkene substrates.
• This work opens new avenues for catalytic transformations using CO2 as a C1 feedstock.