Chemo‐ and Regiodivergent Allyl‐Propargyl Cross‐Coupling Reactions for the Construction of 1,4‐Enallenes and 1,5‐Enynes

Catalyst-controlled divergent transformations represent a vital strategy for the efficient production of structurally diverse molecules from the same readily available precursors. Herein, we report the palladium/phosphine-catalyst-driven chemo- and regiodivergent allyl-propargyl cross-coupling of propargyl carbonates with allyl boronates. Density functional theory (DFT) calculations reveal that the bidentate phosphine ligand plays a crucial role in determining the relative favorability of possible reductive elimination modes from the ƞ3-allyl-ƞ1-allenyl palladium intermediate species. Specifically, MeO-BIPHEP facilitates the 1,1'-reductive elimination to form the 1,4-enallenes; in contrast, XantPhos favors the formation of 1,5-enynes through a 3,3'-reductive elimination pathway.