Department of Organic Chemistry, Faculty of Sciences, University of Malaga, Campus de Teatinos s/n 29071, Malaga, Spain.
J Org Chem. 2010 Aug 20;75(16):5526-32. doi: 10.1021/jo100696w.
A new synthetic methodology of asymmetric epoxidation developed in our laboratories has been employed for the stereoselective synthesis of bengamide E (16) and analogues at the terminal olefinic position. In the event, the chiral sulfonium salt 30 was transformed into its corresponding sulfur ylide and reacted with aldehydes 21 and 44 to efficiently provide epoxy amides 31 and 45, respectively. To access the bengamides from these epoxy amides, we combined a synthetic strategy previously reported by us, using an olefin cross metathesis reaction to introduce various alkyl substituents at the terminal olefinic position of amide 33, with reactions mediated by palladium (Negishi or Suzuki couplings) from amide 49. This latter route of introduction of alkyl groups proved to be more efficient than the metathesis approach and allowed access to the generation of a wide array of new bengamide analogues.
我们实验室开发的一种新的不对称环氧化合成方法已被用于在末端烯烃位置进行苯甲酰胺 E（16）及其类似物的立体选择性合成。在该反应中，手性锍盐 30 转化为相应的硫叶立德，并与醛 21 和 44 反应，分别有效地提供环氧酰胺 31 和 45。为了从这些环氧酰胺中获得苯甲酰胺，我们结合了我们之前报道的一种合成策略，使用烯烃交叉复分解反应在酰胺 33 的末端烯烃位置引入各种烷基取代基，并通过钯（Negishi 或 Suzuki 偶联）介导的酰胺 49 的反应。事实证明，这种引入烷基的方法比复分解方法更有效，并允许生成广泛的新型苯甲酰胺类似物。
