Electrophilic Activation of α,β‐Unsaturated Amides: Catalytic Asymmetric Vinylogous Conjugate Addition of Unsaturated γ‐Butyrolactones |
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Authors: | Dr Ming Zhang Dr Naoya Kumagai Prof?Dr Masakatsu Shibasaki |
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Institution: | Institute of Microbial Chemistry (BIKAKEN), Tokyo, Japan), Fax: (+81)?3-3441-7589 |
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Abstract: | Although catalytic asymmetric conjugate addition reactions have remarkably advanced over the last two decades, the application of less electrophilic α,β‐unsaturated carboxylic acid derivatives in this useful reaction manifold remains challenging. Herein, we report that α,β‐unsaturated 7‐azaindoline amides act as reactive electrophiles to participate in catalytic diastereo‐ and enantioselective vinylogous conjugate addition of γ‐butyrolactones in the presence of a cooperative catalyst comprising of a soft Lewis acid and a Brønsted base. Reactions mostly reached completion with as little as 1 mol % of catalyst loading to give the desired conjugate adducts in a highly stereoselective manner. |
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Keywords: | asymmetric catalysis azaindoline butenolide conjugate addition cooperative catalysis |
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