[3]Dendralene Synthesis: Rhodium(III)‐Catalyzed Alkenyl CH Activation and Coupling Reaction with Allenyl Carbinol Carbonate

[3]DendrAl(l)ene! A new synthesis of [3]dendralenes is based on a Rh(III) -catalyzed alkenyl CH activation and coupling reaction with allenyl carbinol carbonates (see scheme; DG=directing group). A variety of [3]dendralenes with diverse substitution patterns are accessible with good efficiency. The reaction is highly stereoselective and compatible with different directing groups and numerous functional groups.