Transannular Nitrone Cycloaddition. A Stereocontrolled Entry to the Spirocyclic Core of Pinnaic Acid
作者:James D. White、Paul R. Blakemore、Eric A. Korf、Alexandre F. T. Yokochi
DOI:10.1021/ol000361j
日期:2001.2.1
[figure: see text] Thermolysis of lactone 18 initiated a stereospecific transannular nitrone-olefin [3 + 2] cycloaddition to yield tetracycle 19. Methanolysis followed by reductive cleavage of the isoxazolidine yielded 20, representing the azaspirocyclic core of pinnaic acid (1).
[图:见正文]内酯18的热解引发了立体有择的环式环戊烯-烯烃[3 + 2]的环加成反应,生成四环19。进行甲醇解反应,然后还原裂解异恶唑烷,生成20,代表松果酸的氮杂螺环核心(1)。