Highly Efficient Asymmetric Synthesis of beta-Amino Acid Derivatives via Rhodium-Catalyzed Hydrogenation of beta-(Acylamino)acrylates

Highly enantioselective hydrogenation of (E)-beta-(acylamino)acrylates catalyzed by Rh(i)-complexes of electron-rich P-chirogenic diphosphines

Excellent enantioselectivities up to 99.7% were achieved in the hydrogenation of (E)-beta-(acylamino)acrylates by the use of Rh(I)-complexes of electron-rich diphosphines, t-Bu-BisP and t-Bu-MiniPHOS. Low-temperature NMR experiments testify that monohydrides with beta-carbon atom of the substrate bound to rhodium are involved in the catalytic cycle.

N-Benzylhydroxylamine addition to beta-aryl enoates. Enantioselective synthesis of beta-aryl-beta-amino acid precursors

Chiral Lewis acid catalyzed N-benzylhydroxylamine addition to pyrrolidinone-derived enoates afforded beta-aryl-beta-amino acid derivatives in high enantiomeric purity with moderate to very good chemical efficiency.