A new strategy for the synthesis of substituted dihydropyrones and tetrahydropyrones via palladium-catalyzed coupling of thioesters
作者:Haruhiko Fuwa、Kana Mizunuma、Seiji Matsukida、Makoto Sasaki
DOI:10.1016/j.tet.2011.03.114
日期:2011.7
In this paper, we describe a new strategy for the synthesis of substituted dihydropyrones and tetrahydropyrones. By exploiting palladium-catalyzed coupling of thioesters with terminal alkynes or alkenylboronic acids, a variety of β-hydroxy ynones or enones, respectively, could be prepared in an efficient manner under mild conditions. AgOTf-promoted intramolecular oxa-conjugate cyclization of β-hydroxy
在本文中,我们描述了一种合成取代的二氢吡喃酮和四氢吡喃酮的新策略。通过利用钯催化的硫酯与末端炔烃或烯基硼酸的偶联,可以在温和的条件下以有效的方式分别制备各种β-羟基炔酮或烯酮。AgOTf促进的β-羟基炔酮的分子内氧杂共轭环化反应以极好的收率提供了2,6-取代的二氢吡喃酮。另一方面,β-羟基烯酮的酸催化环化由于其可逆性质而导致产物2,6-取代的四氢吡喃酮的外消旋化。最终,发现取代的二氢吡喃酮的立体选择性加氢是合成2,6-顺式的坚实而有效的方法-取代的四氢吡喃酮衍生物。