In this Letter, an efficient synthetic route to prepare polysubstituted thiophene derivatives was achieved via the Et₃N-mediated (Claisen) rearrangement reaction from α-oxo S-methyl-S-propargyl ketenes, which were obtained through alkylation of β-oxodithioesters with propargylic bromides, followed by regioselective intramolecular cyclization.

中文翻译：

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Et3N介导的α-氧代乙烯酮二硫缩醛合成多取代噻吩

在这封信中，通过Et ₃ N介导的α-氧代S-甲基-S-炔丙基烯酮的Et ₃ N介导的（克莱森）重排反应，获得了制备多取代噻吩衍生物的有效合成路线，该反应是通过将β-氧代二硫代酯与炔丙基溴，然后进行区域选择性分子内环化。