An efficient multi‐component synthesis of highly functionalized 2,2′‐bifurans and 2‐(thiophen‐2‐yl)furans is described. A mixture of furan‐ or thiophene‐2‐carbonyl chloride, an isocyanide, and a dialkyl acetylenedicarboxylate undergoes a smooth addition reaction in dry CH₂Cl₂ at ambient temperature to produce 2‐amino‐5‐(4‐chlorofuran‐2‐yl)furan‐3,4‐dicarboxylates and 2‐amino‐5‐(4‐chlorothiophen‐2‐yl)furan‐3,4‐dicarboxylates. A single‐crystal X‐ray‐analysis of a derivative conclusively confirms the structure of these 2,2′‐bifurans and 2‐(thiophen‐2‐yl)furans. A novel electrophilic aromatic substitution reaction can justify the formation of the Cl‐substituted furan or thiophene rings.

中文翻译：

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呋喃或噻吩-2-羰基氯化物，异氰酸酯和乙炔二羧酸二烷基酯之间的反应：2,2'-呋喃和2-（噻吩-2-基）呋喃的多组分合成

描述了高度官能化的2,2'-呋喃和2-（噻吩-2-基）呋喃的高效多组分合成方法。呋喃或噻吩-2-碳酰氯，异氰化物和乙酰二羧酸二烷基酯的混合物在室温下于干燥的CH ₂ Cl ₂中进行平稳加成反应，生成2-氨基-5-（4-氯呋喃-2-烷基）呋喃-3,4-二羧酸酯和2-氨基-5-（4-氯噻吩-2-基）呋喃-3,4-二羧酸酯。衍生物的单晶X射线分析最终确定了这些2,2'-呋喃和2-（噻吩-2-基）呋喃的结构。一种新颖的亲电子芳族取代反应可以证明形成Cl取代的呋喃或噻吩环。