Brønsted Acid Catalyzed Phosphoramidic Acid Additions to Alkenes: Diastereo- and Enantioselective Halogenative Cyclizations for the Synthesis of C- and P‑Chiral Phosphoramidates

The first highly diastereo- and enantioselective additions of a halogen and phosphoramidic acid to unactivated alkenes have been developed, catalyzed by a chiral Brønsted acid. A unique feature of these additions is the opportunity for stereocontrol at two noncontiguous chiral centers, carbon and phosphorus, leading to cyclic P-chiral phosphoramidates. In addition to their inherent value, the phosphoramidates are precursors to enantioenriched epoxy allylamines.