In this paper, we describe the silver triflate/p-toluenesulfonic acid co-catalysed synthesis of seventeen isocoumarins and two thieno[2,3-c]pyran-7-ones starting from 2-alkynylbenzoates and 3-alkynylthiophene-2-carboxylates, respectively. The reaction proceeds with absolute regioselectivity under mild reaction conditions and low catalyst loading, to afford the desired products in good to excellent yields. A conceivable reaction mechanism is proposed and supported by isotope-exchange tests, ¹H NMR studies and ad hoc experiments.

中文翻译：

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三氟甲磺酸银/ p -TSA催化从2-炔基苯甲酸酯合成3-取代的香豆素†

在本文中，我们描述了三氟甲磺酸银/对甲苯磺酸共催化合成17个异香豆素和两个由2-炔基苯甲酸酯和3-炔基噻吩-2-羧酸酯组成的噻吩并[2,3 - c ]吡喃-7-，分别。反应在温和的反应条件下和低的催化剂载量下以绝对的区域选择性进行，以良好至极好的收率提供所需的产物。提出了一种可能的反应机理，并得到了同位素交换试验，¹ H NMR研究和特别实验的支持。