important building blocks for the synthesis of biologically active molecules and can easily be accessed via Beckmann rearrangement of cyclobutanones. However, Beckmann fragmentation is often a competing reaction for these strained ketones. We found that performing the Beckmann rearrangement with Tamura’s reagent in the presence of aqueous HCl suppresses the undesired fragmentation reaction. This improved
γ-内酰胺是
生物活性分子合成的重要组成部分,可以通过
环丁酮的贝克曼重排轻松获得。然而,贝克曼裂解通常是这些应变酮的竞争反应。我们发现,在
盐酸水溶液存在下用田村试剂进行贝克曼重排可抑制不希望的裂解反应。将该改进的方法应用于提供单环,双环,
三环或螺环内酰胺的多种底物。 我们的实验结果和DFT计算表明,重排的机制可能涉及四面体中间体,并且不像经典贝克曼重排那样通过
肟裂解进行。