Transition metal complex catalyzed carboxylation reactions with CO2

• Transition metal catalyzed carboxylation reactions with CO2 have been reviewed.
• Reaction mechanisms and the role of metal complexes have been discussed.
• Ligands are important in most of these catalytic systems.
• Metal–carbon bonds are key intermediates for CO2 insertion.

Transition metal complexes play a key role in catalytic carboxylation reactions with CO2. Various metal complex catalytic systems have been developed for the carboxylation of different substrates that provide versatile methodologies for green organic synthesis. This review summarizes recent developments of CO2 carboxylation reactions with CC bond formation catalyzed by transition metal complexes. The contents in this review are arranged based on various transition metals and substrates of various functional groups. The reaction mechanisms and the role of metal catalysts will also be discussed.