Concise, diastereoconvergent synthesis of endiandric-type tetracycles by iterative cross coupling
作者:Eun Bin Go、Shannon P. Wetzler、Lee Joon Kim、Arthur Y. Chang、David A. Vosburg
DOI:10.1016/j.tet.2016.02.040
日期:2016.6
just seven steps each (longest linear sequence) from Burke's commercial cis-2-bromovinylboronic acid MIDA ester. Three iterative Suzuki–Miyaura couplings using MIDA boronates, including the first such example of a Z–Z coupling, trigger an 8π/6π-electrocyclization cascade. The mixture of endo and exo bicycles thus formed are elaborated into tetracycles via Horner–Wadsworth–Emmons and Diels–Alder reactions
从伯克的商业顺式-2-溴乙烯基硼酸MIDA酯中,仅需七个步骤(最长的线性序列)就可以制备出具有辛二酸型天然产物特征的融合和桥接四环支架。三种使用MIDA硼酸盐的Suzuki-Miyaura迭代偶联,包括第一个Z-Z偶联实例,触发了8π/6π电环化级联。通过霍纳-沃兹沃思-埃蒙斯和狄尔斯-阿尔德反应将由此形成的内含和外含自行车的混合物精制为四轮车。在此过程中,内切和外切非对映体相互转化,以最终提供所需的产品。