Ring‐Opening Reaction of Vinylidenecyclopropanediesters Catalyzed by Re₂(CO)₁₀ or Yb(OTf)₃

Ring‐opening reaction of vinylidenecyclopropanediesters catalyzed by Re 2 (CO) 10 or Yb(OTf) 3 afforded 2 H ‐pyran‐2‐one derivatives or α,β‐unsaturated ketones in moderate to good yields through a highly regioselective carbon–carbon bond cleavage pathway. The substituents at the cyclopropane mainly determine the regioselectivity of the carbon–carbon bond cleavage, providing different products of tandem ring‐opening and rearrangement reactions.