A Photocycloaddition/Fragmentation Approach toward the 3,12-Dioxatricyclo[8.2.1.0^6,13]tridecane Skeleton of Terpenoid Natural Products

Starting from tetronate 1 (R = CH2OH), a short photochemical access to the 3,12-dioxatricyclo[8.2.1.06,13]tridecane-skeleton 2 of briarellin and asbestinin diterpenes has been explored. In the course of these studies, a number of surprising observations were made. For example, a two-step reaction pathway to the bicyclic ketolactone 3 was discovered, which is based on tetronate 1 (R = COOMe).以特罗内酯（tetronate）1（R = CH₂OH）为起始原料，本研究探索了一条简洁的光化学合成路径，以获取布里阿雷林（briarellin）与石棉珊瑚二萜（asbestinin）的3,12-二氧杂三环[8.2.1.0⁶,¹³]十三烷骨架2。在本研究过程中，我们观测到了多项意外现象。例如，基于特罗内酯1（R = COOMe），我们发现了一条可制备双环酮内酯3的两步反应路径。