Synthesis of the Bicyclic Lactone Core of Leonuketal, Enabled by a Telescoped Diels–Alder Reaction Sequence
作者:Phillip S. Grant、Margaret A. Brimble、Daniel P. Furkert
DOI:10.1002/asia.201800903
日期:2019.4.15
The Diels–Alder cycloaddition reaction has become established as a fundamental approach for the preparation of complex natural products; however, successful application of the intermolecular Diels–Alder cycloaddition reaction to the synthesis of particularly congested scaffolds remains surprisingly problematic. Inspired by the terpenoid spiroketal natural product leonuketal, a challenging telescoped
狄尔斯-阿尔德环加成反应已成为制备复杂天然产物的基本方法。然而,分子间Diels-Alder环加成反应在特别拥挤的支架合成中的成功应用仍然令人惊讶。受萜类螺旋体天然产物leonuketal的启发,已经实现了具有挑战性的伸缩反应序列,以访问核心[2.2.2]-双环内酯环系统及其[3.2.1]异构体。我们的四步,无保护组的过程需要进行详细的调查,以规避加合物碎片和中间不稳定的问题。成功解决这些实际问题,并明确确定目标结构,