Selective and Catalytic Hydrocarboxylation of Enamides and Imines with CO2 to Generate α,α-Disubstituted α-Amino Acids

The first catalytic hydrocarboxylation of enamides and imines with CO2 to generate valuable alpha,alpha-disubstituted alpha-amino acids is reported. Notably, excellent chemo- and regio-selectivity are achieved, significantly different from previous reports on beta-carboxylation of enamides, homocoupling or reduction of imines. Moreover, this transition-metal-free procedure exhibits low loading of an inexpensive catalyst, easily available substrates, mild reaction conditions, high efficiency, facile scalability and easy product derivatization, providing great potential for application in organic synthesis, pharmaceutical chemistry, and biochemistry.