Copper‐Catalyzed Enantioselective and Regiodivergent Allylation of Ketones with Allenylsilanes

Abstract We report herein a regiodivergent and enantioselective allyl addition to ketones with allenylsilanes through copper catalysis. With the combination of CuOAc, a Josiphos‐type bidentate phosphine ligand and PhSiH3, allyl addition to a variety of ketones furnishes branched products in excellent enantioselectivities. The regioselectivity is completely reversed by employing the P‐stereogenic ligand BenzP*, affording the linear products with excellent enantioselectivities and good Z‐selectivities. The linear Z‐product could be converted to E‐product via a catalytic geometric isomerization of the Z‐alkene group. The silyl group in the products could provide a handle for downstream elaboration.