Copper( <scp>i</scp> )-catalyzed asymmetric addition of diarylphosphine sulfides to aldimines

Herein, we report a copper(I)-catalyzed enantioselective addition of diarylphosphine sulfides to <i>N</i>-thiophosphinoyl aldimines. The reaction offers some advantages, such as mild conditions, an easy protocol, and high enantioselectivity. Control experiments indicate that the "soft-soft" interactions between the copper(I) catalyst and the sulfur atoms in both diarylphosphine sulfides and <i>N</i>-thiophosphinoyl aldimines facilitate the addition.