Synthesis of Enantiopure Metal-Chelating Noncanonical Amino Acids via Negishi Cross-Coupling.

Herein, we report the synthesis of a new class of noncanonical α-amino acids bearing metal-chelating functionalities through Negishi cross-coupling between iodinated serine- or homoserine-derived substrates and pyridyl or polypyridyl partners. The method provides straightforward access to gram-scale quantities of amino acids bearing a range of nitrogen-based chelating ligands, including pyridine, bipyridine, phenanthroline, and terpyridine motifs, without detectable racemization throughout the reaction sequence.