The direct carboxylation of terminal alkynes with carbon dioxide.

A simple and straight-forward method has been developed for direct carboxylation of terminal alkynes using CO2as the C1 carbon feedstock. The direct C–H bond functionalization is achieved with Cs2CO3as the base and in the absence of transition metal catalyst. Various propiolic acids were synthesized in good to excellent yields with a wide substrate scope and a good functional groups tolerance. This is a more atom- and step-economic protocol with great potential in practical application. [ABSTRACT FROM AUTHOR]