Ligand‐ and Base‐Free Cu II ‐Mediated Selective S ‐Arylation of α‐Enolic Dithioesters by Chan–Lam Coupling at Room Temperature

The ligand‐ and base‐free copper(II)‐mediated Chan–Lam cross‐coupling of arylboronic acids with α‐enolic dithioesters has been achieved at room temperature under aerobic neutral conditions to afford unsymmetrical α‐oxoketene S , S ‐acetals for the first time. This operationally simple, mild protocol tolerates a wide range of arylboronic acids and α‐enolic dithioesters. Typical features of this novel strategy include short reaction times (5 min), good yields and highly selective C=S functionalization leading to S ‐arylation in one pot.