抄録
A general catalytic allylation of simple ketoimines was developed using 1 mol % of CuF(PPh3)3 as catalyst, 1.5 mol % of La(OiPr)3 as the cocatalyst, and stable and nontoxic allylboronic acid pinacol ester as the nucleophile. This reaction constituted a good template for developing the first catalytic enantioselective allylation of ketoimines. In this case, using LiOiPr as the cocatalyst produced higher enantioselectivity and reactivity than La(OiPr)3. Thus, using the CuF-cyclopentyl-DuPHOS complex (10 mol %) and LiOiPr(30 mol %) in the presence of tBuOH (1 equiv) produced high enantioselectivity up to 93% ee from range of aromatic ketoimines. Mechanistic studies indicated that LiOiPr accelerates the reaction by increasing the concentration of an active nucleophile, allylcopper.
