Stereoselective Convergent Synthesis of a <i>trans</i>-Fused Polycyclic Ether Ring System Including a 4-Hydroxy-5-methyl-tetrahydropyran Ring
作者:Keisuke Suzuki、Tadashi Nakata
DOI:10.1021/ol026261q
日期:2002.8.1
[reaction: see text] Stereoselective convergent synthesis of a trans-fused 6-6-6-6-membered tetracyclic ether ring system including 4alpha- or 4beta-hydroxy-5-methyl-tetrahydropyran was achieved. The key reactions involve the acetylide-aldehyde coupling of two tetrahydropyrans, intramolecular hetero-Michael cyclization of enone, stereoselective reduction of enone, hydroboration, intramolecular acetalization
[反应:见正文]实现了包括4α-或4β-羟基-5-甲基-四氢吡喃的反式稠合6-6-6-6元四环醚环系统的立体选择性会聚合成。关键反应包括两个四氢吡喃的乙炔-醛偶联,烯酮的分子内杂-迈克尔环化,烯酮的立体选择性还原,硼氢化,分子内缩醛化和用Et(3)SiH-TMSOTf缩醛的立体选择性还原。