Bismuth- and Iron-Catalyzed Three-Component Synthesis of α-Amino Acid Derivatives: A Simple and Convenient Route to α-Arylglycines

Efficient bismuth- and iron-catalyzed three-component syntheses of α-arylglycines have been developed. These methods provide a general, atom-economic route to various N-protected α-arylglycines starting from readily available amides (or carbamates), glyoxalates, and (hetero)arenes with water as the only by-product. Scope and limitations of bismuth- and iron-catalyzed reactions are discussed and compared. In addition, mechanistic investigations as well as initial forays into stereoselective three-component reactions are presented.