The synthesis of stilbenoids and styryl carboxylic acids is accomplished with high E-stereoselectivity by olefination of aldehydes with thiophthalides under basic conditions. The olefination is highly atom-efficient as it only loses elemental sulfur during the reaction. This olefination, in conjunction with retro Kolbe–Schmitt reaction, allows facile synthesis of E-hydroxystilbenoids with minimal employment of protecting groups. This study also discloses two important findings: formation of i) 4-methylsulfanyl isocoumarins and ii) an 2-arylindenone.
在碱性条件下,通过
硫代
邻苯二甲酸酯对醛进行烯化反应,可以高E-立体选择性地合成
芪类化合物和
苯乙烯基
羧酸。该烯化反应具有高度的原子效率,因为在反应过程中仅损失了元素
硫。这种烯化反应与逆科尔比-施密特反应相结合,能够简便地合成E-羟基
芪类化合物,并最小程度地使用保护基团。这项研究还揭示了两个重要发现:i) 形成4-甲
硫基异
香豆素和ii) 形成2-芳基
茚满酮。