Highly Enantioselective Decarboxylative Protonation of α-Aminomalonates Mediated by Thiourea <i>Cinchona</i> Alkaloid Derivatives: Access to Both Enantiomers of Cyclic and Acyclic α-Aminoacids
Thiourea derived cinchona alkaloids promote the asymmetric decarboxylative protonation of cyclic, acyclic, or bicyclic alpha-aminomalonate hemiesters under mild and metal-free conditions to afford enantioenriched aminoesters in high yields and enantioselectivities up to 93%. Both enantiomers of the aminoesters have been synthesized with the same selectivity when using organic base 3 and its pseudoenantiomer