Organocatalytic Enantioselective Higher-Order Cycloadditions of In Situ Generated Amino Isobenzofulvenes
作者:Bjarke S. Donslund、Alicia Monleón、Teresa A. Palazzo、Mette Louise Christensen、Anne Dahlgaard、Jeremy D. Erickson、Karl Anker Jørgensen
DOI:10.1002/anie.201710694
日期:2018.1.26
The [8+2] cycloaddition of indene‐2‐carbaldehydes and nitro olefins is described to provide benzonorbornene scaffolds in a highly peri‐, diastereo‐, and enantioselective fashion in the presence of a C2‐symmetric aminocatalyst. This reaction, which proceeds through a transient semi‐aromatic amino isobenzofulvene, represents the first example of catalytic formation and transformation of these species
据描述,在C 2对称氨基催化剂存在下,茚2甲醛和硝基烯烃的[8 + 2]环加成反应可提供高苯并降冰片烯骨架,高对映异构,非对映异构和对映选择性的形式。该反应通过瞬态半芳族氨基异苯并富烯进行,代表了这些物质催化形成和转化的第一个例子。量子化学计算表明了动力学控制的逐步机制,其中立体化学是在第一次形成键的事件中确定的。除了有用的[8 + 2]环加合物外,[10 + 4]环加合物在计算机上已被确定为潜在的非通路中间体。