Department of Biology and Chemistry, Nipissing University, North Bay, ON, P1B 8L7, Canada.
Mol Divers. 2013 Nov;17(4):827-34. doi: 10.1007/s11030-013-9470-x. Epub 2013 Aug 15.
A one-step Bronsted acid-catalyzed synthetic methodology leading to 3-(alkoxymethylene)indolin-2-ones was developed starting from easily accessible 2-hydroxyindole-3-carboxaldehydes. The procedure simply involves a treatment of differently substituted 2-hydroxyindole-3-carboxaldehydes with various alcohols (primary/secondary/tertiary/allyl/propargyl/benzyl) in the presence of a catalytic amount of Bronsted acids such as [Formula: see text]-toluenesulfonic acid and trifluroacetic acid. A series of 19 indolin-2-one-based enol-ethers were synthesized in excellent yields, which implies the general character of our methodology. The enol-ethers produced could be used as a useful building block for the synthesis of indole-based heterocycles.
发展了一种由易得的 2-羟基吲哚-3-甲醛出发，经一步Bronsted 酸催化合成 3-(烷氧亚甲基)吲哚啉-2-酮的方法。该方法只需在Bronsted 酸（如对甲苯磺酸和三氟乙酸）催化量存在下，用各种醇（伯/仲/叔/烯丙基/炔丙基/苄基）处理不同取代的 2-羟基吲哚-3-甲醛。以优异的收率合成了一系列 19 个基于吲哚啉-2-酮的烯醚，这表明了我们方法的通用性。所得到的烯醚可用作合成基于吲哚的杂环的有用砌块。
