title: Pd(0)-catalyzed alkene oxy- and aminoalkynylation with aliphatic bromoacetylenes.
abstract: Tetrahydrofurans and pyrrolidines are among the most important heterocycles found in bioactive compounds. Cyclization-functionalization domino reactions of alcohols or amines onto olefins constitute one of the most efficient methods to access them. In this context, oxy- and aminoalkynylation are especially important reactions, because of the numerous transformations possible with the triple bond of acetylenes, yet these methods have been limited to the use of silyl protected acetylenes. Herein, we report the first palladium-catalyzed oxy- and aminoalkynylation using aliphatic bromoalkynes, which proceeded with high diastereoselectivity and functional group tolerance. A one-pot hydrogenation of the triple bond gave then access to alkyl-substituted tetrahydrofurans and pyrroldines. Finally, a detailed study of the side products formed during the reaction gave a first insight into the reaction mechanism.
authors.affiliation: Laboratory of Catalysis and Organic Synthesis, Ecole Polytechnique Fédérale de Lausanne, EPFL SB ISIC LCSO, BCH 4306, 1015 Lausanne, Switzerland.
authors.forename: Stefano
authors.initials: S
authors.lastname: Nicolai
authors.forename: Raha
authors.initials: R
authors.lastname: Sedigh-Zadeh
authors.forename: Jérôme
authors.initials: J
authors.lastname: Waser
mesh_terms: D000475:Alkenes / Q000737:chemistry*; D000480:Alkynes / Q000737:chemistry*; D000588:Amines / Q000737:chemistry*; D002384:Catalysis; D003500:Cyclization; D005663:Furans / Q000737:chemistry*; D006865:Hydrogenation; D015394:Molecular Structure; D010165:Palladium / Q000737:chemistry*; D011759:Pyrrolidines / Q000737:chemistry*
chemical_list: D000475:Alkenes; D000480:Alkynes; D000588:Amines; D005663:Furans; D011759:Pyrrolidines; D010165:Palladium