螺旋雙環及螺旋雙環醚之合成

Abstract

我們利用本實驗室已成熟發展的鋅銅試劑製備出3-(2-酯烴)環己烯酮，再經由硼氫化鈉還原羰基、間氯過氧苯甲酸對雙鍵進行環氧化反應，以此環氧基衍生物在-78 °C下利用LHMDS進行環化反應，得到具有立體選擇性的單一動力學產物。 將3-(2-酯烴)環己烯酮以二異丁基鋁進行還原，同時還原羰基及酯基官能基，再以間氯過氧苯甲酸進行環氧化，及環化的一鍋化反應，得到帶有氧原子的螺旋雙環醚化合物。 具有雜原子及螺旋結構的天然物十分常見，利用本實驗室的環化反應所得到的螺旋化合物，亦是天然物當中常見的片段，我們保留了兩個羥基，可被用來進行氧化或取代反應，作為官能基的延伸，或當成天然物全合成的步驟參考。We use the well-known Zinc-Copper reagents, which was established by our group, to prepare the 3-substutied cyclohexenone, then followed by the reduction by sodium boron hydride, and epoxidation by mCPBA to yield the starting material. By using LHMDS under -78 °C we demonstrated the cyclization by the derivatives of epoxy in mono kinetic product with stereoselectivity. With cyclohexenone starting material in hand. We reduced the carbonyl group and ester by DIBAL-H to yield the diol. And then, the spiro ether was generated by epoxidation of the diol and cyclized in one pot. Organic compounds with heteroatom and spiro building block are common in nature product. The spiro products, which were prepared by our group, contain the fragments of some nature products. That can also be modified by oxidation or substitution of the diol to expend the application.