Base catalysed rearrangements of 4-hydroxyphenyl allyl ethers: syntheses of alliodorin and alliodorol
作者:Laurence M. Harwood、Anona J. Oxford、Colin Thomson
DOI:10.1039/c39910001303
日期:——
4-hydroxyphenyl allyl ethers 1a–e in refluxing aqueous methanol in the presence of KOH and oxygen furnish 2-substituted 1,4-dihydroxybenzene derivatives; products 2a,b and 3c are derived via base catalysed Claisen rearrangement, whereas presence of 3′-substitution on the allylic moiety disfavours this pathway, leading to formation of products 4b–c, consistent with the operation of base catalysed tandem [2,3]-
在KOH和氧气存在下,在回流的甲醇水溶液中,将4-羟基苯基烯丙基醚1a-e提供2-取代的1,4-二羟基苯衍生物;产物2a,b和3c是通过碱催化的克莱森重排衍生而来的,而烯丙基部分3'取代的存在不利于该途径,导致形成产物4b–c,与碱催化的串联反应操作一致[2,3 ]-并应对重排;后一种方法已应用于异狄氏菌素和异狄氏甾醇(Cordia alliodora的心材成分)的全合成。