Efficient and Practical Ag-Catalyzed Cycloadditions between Arylimines and the Danishefsky Diene

摘要: An efficient Ag-catalyzed method for asymmetric addition of the Danishefsky diene to various aryl imines afford cycloadducts in ≥89% ee and ≥85% isolated yield is reported. Reactions are effected with 0.1−1 mol % catalyst (4 °C), chiral ligand readily prepared from commercially available materials, including inexpensive i-Leu. These catalytic cycloadditions can be carried out without use solvent or undistilled THF air. A first generation supported that effectively promotes cycloaddition reaction recycled (five cycles) described.