Amidine‒ and guanidine‒based synthetic methods for CO2 capture and utilization

The microreview presents an overview of the very recent advances (2020 to September, 2022) in amidine‒ and guanidine‒based synthetic methods for carbon dioxide capture and utilization. The use of amidine and guanidine superbases has proved to greatly favor CO2 capture by amines, as superbases are able to promote the formation of relatively stable carbamate salts. Moreover, such superbases are also able to activate simple alcoholic substrates toward CO2 capture, through deprotonation of the hydroxyl group followed by CO2 attack with formation of carbonate salts. Recent progress in this field is discussed in the first part of the microreview. The capacity of amidine and guanidine superbases to promote the formation of carbamate and carbonate salts from CO2 and amines or alcohols, respectively, has also opened the way to the efficient incorporation of CO2 into suitably functionalized organic substrates. Some important representative examples are discussed in the second part of the microreview.