Copper-Catalyzed Direct C(sp 3 )-H Alkoxylation to Access Quaternary α-Alkoxylated Amino Acid Derivatives.

A copper-catalyzed C(sp(3))-H alkoxylation was developed to prepare quaternary alpha-alkoxylated amino acid derivatives in good yields. This protocol can be applied to a series of alpha-amino acids bearing a variety of functional group substituents. Facile removal of the auxiliary directing group and tolerance of condensation conditions for amide bond formation enable the potential application of this method in the discovery of new peptide drugs in the future.