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We report the first direct catalytic enantioselective allylation of acyclic α-ketiminoesters to afford α-allyl-α-aryl and α-allyl-α-trifluoromethyl amino esters in excellent isolated yield (91−99%) and with high optical purity (90−99+% ee). The allylation proceeds on a gram scale with 5−10 mol % of indium(I) iodide and commercially available BOX-type ligands. The allylated products are easily converted to enantiomerically enriched α-substituted proline derivatives.

A short formal synthesis of ent-Cephalotaxine is achieved. The approach features a new Lewis acid-mediated [2,3]-Stevens rearrangement of N-allylated prolineamide to generate a key quaternary stereogenic center. Additionally, a one-pot Parham-aldol sequence was developed to rapidly assemble two of the four rings in the cephalotaxine core.

Both metal-catalyzed and organocatalytic transfer hydrogenation reactions are widely employed for the reduction of C=O and C=N bonds. However, selective transfer hydrogenation reactions of C=C bonds remain challenging. Therefore, the...

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