Palladium-Catalyzed Oxidative Aminocarbonylation of Alkynols

Alkynols undergo palladium-catalyzed aminocarbonylation leading to the direct formation of different heterocyclic de-rivatives, depending on the position of the –OH group with respect to the triple bond. In the case of 4-yn-1-ols 1 and (Z)-2-en-4-yn-1-ols 4, the initially formed 2-ynamide intermediates 2 and 5, respectively, undergo cyclization leading to tetrahydrofuran derivatives 3 or 2-furan-2-ylacetamides 7, respectively. In the case of 2-yn-1-ols 8, the aminocarbonylation products 9 undergo intermolecular conjugate addition, followed by lactonization, leading to aminofuranones 11.