A convenient asymmetric synthesis of the unnatural amino acid 2,6-dimethyl-L-tyrosine

Article abstract of DOI:10.1055/s-1992-26212

The title compound was prepared in high optical purity by a five-step synthesis from 3,5-dimethylphenol on a kilogram scale. The key steps were a modified palladium-catalyzed coupling of an aryl iodide with methyl 2-acetamidoacrylate and hydrogenation of the resulting sterically hindered dehydroamino acid 4 using [Rh(1,5-COD)(R,R-DIPAMP)]BF₄ as catalyst.