Syntheses of α-Amino Acids by Using CO as a C1 Source.

The incorporation of CO into organic compounds is currently one of the most active research topics in organic chemistry, because CO is an abundant, inexpensive, nontoxic, and renewable C1 source. However, CO is also a thermodynamically stable and kinetically inert gaseous compound, and as such, special strategies are required to activate CO 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 . In this Minireview, we summarize recent synthetic methods for α-amino acids that use CO as a carboxylic acid unit.