Functionalized Tetrahydropyridines by Enantioselective Phosphine-Catalyzed Aza-[4 + 2] Cycloaddition of <i>N</i>-Sulfonyl-1-aza-1,3-dienes with Vinyl Ketones
作者:Huamin Wang、Wei Zhou、Mengna Tao、Anjing Hu、Junliang Zhang
DOI:10.1021/acs.orglett.7b00489
日期:2017.4.7
The development of electron-demand disfavored [4 + 2] cycloaddition of two electron-deficient reacting partners poses a considerable challenge. An enantioselective aza-[4 + 2] cycloaddition of electron-deficient N-sulfonyl-1-aza-1,3-dienes is possible with vinyl ketones via phosphine catalysis, which provides facile access to a wide range of enantioenriched trifluoromethylated tetrahydropyridines in
两种电子不足的反应伙伴对电子需求不利的[4 + 2]环加成反应的发展提出了相当大的挑战。电子缺陷的N-磺酰基-1- aza-1,3-二烯的对映选择性aza- [4 + 2]环加成反应可通过膦催化与乙烯基酮反应,从而可轻松地从顶部获得大量对映体富集的三氟甲基化四氢吡啶ee达到97%时,ee达到97%,dr> 20:1。机理研究表明,该环加成反应通过串联的分子间氮杂-Rauhut-Currier /分子内氮杂-Michael加成反应进行。