Reactions of 3-(1-Hydroxyalkyl)phthalides with Acids: Synthesis of (<i>Z</i>)-3-Alkylidenephthalides and 3-Alkyl-8-hydroxyisocoumarins
作者:Raghao S. Mali、Kantipudi N. Babu
DOI:10.1021/jo971622e
日期:1998.4.1
acid-catalyzed method for the synthesis of (Z)-3-butylidenephthalides 5 and a novel and general route to 3-alkyl-8-hydroxy/methoxyisocoumarins 6-8 from phthalides 9 is described. The hydroxyphthalides 4 and 10 were obtained by condensation of the phthalide anion with butyraldehyde and acetaldehyde. Reaction of hydroxyphthalides 4 with a mixture of orthophosphoric acid and formic acid gave the (Z)-3
描述了一种新的酸催化的合成(Z)-3-丁二烯酞化物5的方法,以及从酞化物9制备3-烷基-8-羟基/甲氧基异香豆素6-8的新颖且通用的路线。通过将邻苯二甲酸酯阴离子与丁醛和乙醛缩合获得羟基邻苯二甲酸酯4和10。羟基邻苯二甲酸酯4与正磷酸和甲酸的混合物反应,得到(Z)-3-丁叉萘二甲酸酯5,而羟基邻苯二甲酸酯4和10与对甲苯磺酸反应生成3-烷基异香豆素6-8。本方法允许异香豆素中3-取代基的变化以及异香豆素和亚烷基萘的芳环上官能化的模式。