Type II Intramolecular [5+2] Cycloaddition: Facile Synthesis of Highly Functionalized Bridged Ring Systems
作者:Guangjian Mei、Xin Liu、Chuang Qiao、Wei Chen、Chuang-chuang Li
DOI:10.1002/anie.201410806
日期:2015.2.2
formation of various highly functionalized and synthetically challenging bridged seven‐membered ring systems (such as bicyclo[4.4.1]undecane, bicyclo[4.3.1]decane, bicyclo[5.4.1]dodecane, and bicyclo[6.4.1]]tridecane). This simple, thermal, direct transformation has a broad substrate scope and is high yielding, with high functional‐group tolerance and unique endo selectivity. The highly strained tricyclic
II型分子内氧化吡啶介导的[5 + 2]环加成反应可有效且非对映选择性地形成各种高度官能化且具有合成挑战性的桥连七元环系统(例如双环[4.4.1]十一烷,双环[4.3.1])癸烷,双环[5.4.1]十二烷和双环[6.4.1]]十三烷)。这种简单,热,直接的转化具有广泛的底物范围,产量高,具有较高的官能团耐受性和独特的内在选择性。使用这种方法可高效合成非对映异构体,其中包括丁二酸丁二醇酯(吡啶)和环柠檬醇的高应变三环核。