Desymmetrizing Asymmetric Ring Expansion of Cyclohexanones with α-Diazoacetates Catalyzed by Chiral Aluminum Lewis Acid
作者:Takuya Hashimoto、Yuki Naganawa、Keiji Maruoka
DOI:10.1021/ja202070j
日期:2011.6.15
in a 2:1 ratio was found to promote novel catalytic asymmetric ring expansion of cyclohexanone with α-substituted α-diazoacetates to give seven-membered rings with an all-carbon quaternary center. Application of this strategy to 4-substituted cyclohexanones opened up a novel way for the catalytic desymmetrizing asymmetric construction of cycloheptanones bearing remote α,δ-chiral centers.
由 Me(3)Al 和 3,3'-双(三甲基甲硅烷基)-BINOL 以 2:1 的比例组成的手性铝路易斯酸催化剂被发现可促进环己酮与 α-取代的 α-重氮乙酸酯的新型催化不对称扩环,得到具有全碳四元中心的七元环。将该策略应用于 4-取代环己酮为带有远程 α,δ-手性中心的环庚酮的催化去对称不对称结构开辟了一条新途径。