Syntheses of α‐Amino Acids by Using CO 2 as a C1 Source

The incorporation of CO 2 into organic compounds is currently one of the most active research topics in organic chemistry, because CO 2 is an abundant, inexpensive, nontoxic, and renewable C1 source. However, CO 2 is also a thermodynamically stable and kinetically inert gaseous compound, and as such, special strategies are required to activate CO 2 and incorporate it into organic compounds. In particular, because the carbon atom adjacent to the nitrogen atom of amine derivatives is positively charged, umpolung carboxylation, which is a difficult chemical process, should be considered for the production of α‐amino acids by using CO 2 . In this Minireview, we summarize recent synthetic methods for α‐amino acids that use CO 2 as a carboxylic acid unit.