Ligand- and Base-Free CuII-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 alpha-enolic dithioesters has been achieved at room temperature under aerobic neutral conditions to afford unsymmetrical alpha-oxoketene S,S-acetals for the first time. This operationally simple, mild protocol tolerates a wide range of arylboronic acids and alpha-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.