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[DPEPhosbcpCu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst
Published on: May 21, 2019
Fe-Catalyzed Selective Cyclopropanation of Enynes under Photochemical or Thermal Conditions
Marie-Idrissa Picher1, Bernd Plietker1
1Institut für Organische Chemie , Universität Stuttgart , Pfaffenwaldring 55 , DE-70569 Stuttgart , Germany.
Abstract:
The nucleophilic Fe-complex Bu4N[Fe(CO)3(NO)] (TBA[Fe]) catalyzes the cyclopropanation of enynes to substituted propargyl cyclopropanes using diazoesters as carbene surrogates. The catalyst can be activated either thermally in the presence of catalytic amounts of 4-nitroanisole or under photochemical conditions. Cyclopropanation occurs selectively at the enyne moiety; alternative olefinic moieties remain intact.
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