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[摘要]:Catalytic asymmetric synthesis of 3-aminooxindoles with a tetrasubstituted carbon stereocenter is described. 1 mol% of homobimetallic (R)-Ni-2-Schiff base complex 1 catalyzed asymmetric amination of 3-alkyl-substituted oxindoles with azodicarboxylates to give products in 89-99% yield and 87-99% ee. For 3-aryl-substituted oxindoles, 10 mol% of (R)-Ni-2-Schiff base complex was required to obtain products in 66-98% ee. Postulated catalytic cycle as well as transformation of the products are also described. |
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