Ying Maben, Roush William R
Department of Chemistry, The Scripps Research Institute, Florida, 130 Scripps Way, Jupiter, FL 33458, USA.
Tetrahedron. 2011 Dec 30;67(52):10274-10280. doi: 10.1016/j.tet.2011.10.029.
A highly stereoselective synthesis of the C(22)-C(36) fragment 2 of reidispongiolide A is described. This synthesis features the highly stereoselective mismatched double asymmetric crotylboration reaction of the aldehyde derived from 5 and the new chiral reagent (S)-(E)-7 that provides 12 with >15:1 d.r. Subsequent coupling of the derived vinyl iodide 3 with aldehyde 16 provided allylic alcohol 17, that was elaborated by three steps into the targeted reidispongiolide fragment 2.
描述了一种瑞德海绵内酯A的C(22)-C(36)片段2的高度立体选择性合成方法。该合成方法的特点是5衍生的醛与新型手性试剂(S)-(E)-7发生高度立体选择性的不匹配双不对称巴豆基硼酸化反应,以大于15:1的非对映体比例得到12。随后,衍生的乙烯基碘3与醛16偶联得到烯丙醇17,再经过三步反应将其转化为目标瑞德海绵内酯片段2。