Catalytic C(sp)-H carboxylation with CO2

Carbon dioxide (CO2) is the dominant greenhouse gas and the most abundant and renewable C1 resource. Therefore, the chemical fixation and conversion of CO2 to high-value chemicals and materials is an intriguing strategy towards carbon neutrality and sustainable chemical industry. The direct carboxylation of C(sp)-H bonds with CO2 has attracted great interest in the last decade as an atom-economic approach to propiolic acids, which have a wide range of applications in pharmaceuticals and advanced materials. This article provides a comprehensive review of this growing field of research. With a brief overview of non-catalytic carboxylation, the focus is on catalytic processes, which overwhelmingly involve metal cat-alysts, homogeneous or heterogeneous. The recently budding organocatalysis is also included. Critical comparisons and mechanism analyses are provided, along with personal perspectives for future studies.(c) 2023 Elsevier B.V. All rights reserved.