gold(I)‐catalyzed cascade cyclization–alkynylation of allenoates using alkynyl bromide to generate β‐alkynyl‐γ‐butenolides was investigated. Whereas alkynyl iodides afforded significant amounts of the homo‐coupling of two lactone units, alkynyl bromides led to a selective reaction, and a broad functional group tolerance was observed. Under the optimized reaction conditions, it was possible to directly synthesize
研究了使用炔基
溴化物生成
金(I)催化的
脲基
甲酸酯的级联环化-炔基化反应,以生成β-炔基-γ-
丁烯酸内酯。炔基
碘提供了大量的两个内酯单元的均偶联,而炔基
溴则导致选择性反应,并且观察到宽泛的官能团耐受性。在优化的反应条件下,可以以中等到良好的产率直接合成大范围的β-炔基-γ-
丁烯内酯,而无需任何外部氧化剂。