Recent progress and challenges in carboxylation with CO2

As well known, carbon dioxide (CO2) is an ideal C1 source in organic synthesis due to its high abundance, low cost, nontoxicity, and renewability. Significant progress has been realized in this field. This minireview summarizes the recent development of carboxylation using CO2 via transition metal catalysis, photoredox catalysis, and electrochemistry, with focus on the advances in the last two years. In this article, we provide a comprehensive introduction of the progress, point out the advantages and limitations, and discuss the potential direction for further development.