Synthetic Studies on Indoles and Related Compounds. XXXIX. New Strategy for Indole Synthesis from Ethyl Pyrrole-2-carboxylate.
作者:Masanobu TANI、Takahiro ARIYASU、Masanori OHTSUKA、Terumi KOGA、Yumi OGAWA、Yuusaku YOKOYAMA、Yasuoki MURAKAMI
DOI:10.1248/cpb.44.55
日期:——
As a synthetic application of the previously reported C4-acylation of ethyl pyrrole-2-carboxylate (1), a new strategy for indole synthesis was developed. Ethyl pyrrole-2-carboxylate (1) was allowed to react with succinic anhydride or 3-methoxycarbonylpropionyl chloride to give, in good yield, a C4-succinyl derivative of 1, which was converted into ethyl 7-oxo-4, 5, 6, 7-tetrahydroindole-2-carboxylate (6) as a key intermediate for indole synthesis. Starting from 6, several indoles functionalized on the benzene moiety were synthesized.
作为之前报道的乙基吡咯-2-羧酸酯(1)C4-酰化反应的综合应用,开发了一种合成吲哚的新策略。乙基吡咯-2-羧酸酯(1)与琥珀酸酐或3-甲氧基羰基丙酰氯反应,以良好产率得到1的C4-琥珀酰衍生物,该衍生物被转化为乙基7-氧代-4,5,6,7-四氢吲哚-2-羧酸酯(6),这是合成吲哚的关键中间体。从6出发,合成了几种在苯环上带有官能团的吲哚化合物。