Synthesis of Filibuvir. Part II. Second-Generation Synthesis of a 6,6-Disubstituted 2<i>H</i>-Pyranone via Dieckmann Cyclization of a β-Acetoxy Ester
作者:Zhihui Peng、John A. Ragan、Roberto Colon-Cruz、Brian G. Conway、Eric M. Cordi、Kyle Leeman、Leo J. Letendre、Li-Jen Ping、Janice E. Sieser、Robert A. Singer、Gregory W. Sluggett、Holly Strohmeyer、Brian C. Vanderplas、Jon Blunt、Nicola Mawby、Kevin Meldrum、Stuart Taylor
DOI:10.1021/op400236r
日期:2014.1.17
drivers behind this change were the modest and variable yields observed in the intramolecular cyclization to generate the β-keto lactone. Changing the cyclization substrate from oxazolidinone to alkyl ester offered a significantly improved cyclization, as well as improvements in the alkyne hydrogenation. Selection of the optimal substrates for methanolysis and intermediate salt formation are also described
本文描述了将恶唑烷酮(3)转化为β-酮内酯(5)的改进顺序。引起这一变化的主要驱动力是在分子内环化反应中产生β-酮内酯时观察到适度和可变的产率。将环化底物从恶唑烷酮改为烷基酯可显着改善环化作用,并改善炔烃加氢反应。还描述了用于甲醇分解和形成中间盐的最佳底物的选择。