PyBidine-Cu(OTf)2-Catalyzed Asymmetric [3+2] Cycloaddition with Imino Esters: Harmony of Cu-Lewis Acid and Imidazolidine-NH Hydrogen Bonding in Concerto Catalysis
PyBidine-Cu(OTf)2-Catalyzed Asymmetric [3+2] Cycloaddition with Imino Esters: Harmony of Cu-Lewis Acid and Imidazolidine-NH Hydrogen Bonding in Concerto Catalysis
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DOI：
10.1002/anie.201410782
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发表时间：
2015-01-26
影响因子：
16.6
通讯作者：
Yamanaka, Masahiro
中科院分区：
文献类型：
--
作者：
Arai, Takayoshi;Ogawa, Hiroki;Yamanaka, Masahiro
A双咪唑烷吡啶（PyBidine）-Cu（OTf）（2）配合物催化硝基烯烃与亚氨基酯的内选择性[3+2]环加成反应，PyBidine-Cu（OTf）（2）的X射线晶体学分析络合物和DFT计算表明，亚氨基酯的中间体Cu烯醇化物与硝基烯烃或亚甲基吲哚啉酮反应，其通过PyBidine-Cu（OTf）（2）催化剂的NH-氢键活化。
A bis(imidazolidine)pyridine (PyBidine)-Cu(OTf)(2) complex catalyzing the endo-selective [3+2] cycloaddition of nitroalkenes with imino esters was applied to the reaction of methyleneindolinones with imino esters to afford spiro[pyrrolidin-3,3'-oxindole]s in up to 98% ee. X-ray crystallographic analysis of the PyBidine-Cu(OTf)(2) complex and DFT calculations suggested that an intermediate Cu enolate of the imino ester reacts with nitroalkenes or methyleneindolinones, which are activated by NH-hydrogen bonding with the PyBidine-Cu(OTf)(2) catalyst.