Catalytic Asymmetric Synthesis of Functionalized α,α-Disubstituted α-Amino Acid Derivatives from Racemic Unprotected α-Amino Acids via in-situ Generated Azlactones

摘要

Masked and activated highly enantioen-riched α,α-disubstituted α-amino acids with an additional adjacent stereocenter were formed by a tandem reaction involving five steps using racemic unprotected amino acid substrates. Key step is the 1,4-addition of in-situ generated azlactones to a broad number of-enones. The products of this step-economic route can, e.g., be useful for a divergent and rapid access to biologically interesting unnatural glutamic acid derivatives.