Reverse Aromatic Cope Rearrangement of 2-Allyl-3-alkylideneindolines Driven by Olefination of 2-Allylindolin-3-ones: Synthesis of α-Allyl-3-indole Acetate Derivatives
The reverse aromatic Cope rearrangement of 2-allyl-3-alkylideneindolines obtained by Horner-Wadsworth-Emmons olefination of 2-allylindolin-3-ones was performed. When 2-allylindolin-3-ones were treated with phosphonium ylides in refluxing toluene, domino Wittig reaction and reverse aromatic Cope rearrangement took place to give alpha-allyl-3-indole acetatederivatives in good yields. The aromatization
Treatment of 2,3-dihydro-1H-indol-3-ones with allyl alcohols in the presence of camphorsulfonic acid and magnesium sulfate at 130 °C gave, via condensation and a Claisen rearrangement, 2-allyl-2,3-dihydro-1H-indol-3-ones in good yields. The stereochemistry of the products was determined by NOE experiments.
2,3- 二氢-1H-吲哚-3-酮与烯丙基醇在樟脑磺酸和硫酸镁存在下于 130 ℃ 处理,通过缩合和克莱森重排,得到 2-烯丙基-2,3-二氢-1H-吲哚-3-酮,收率很高。通过 NOE 实验确定了产物的立体化学性质。