title: [W(CO)5]-catalyzed endo- or exo-cycloisomerization reactions of 1,1-disubstituted 4-pentyn-1-ols: experimental and theoretical studies.
abstract: The [W(CO)5]-catalyzed cycloisomerization reaction of 1,1-disubstituted 4-pentyn-1-ol derivatives has been studied from both, an experimental and theoretical point of view. Three different catalytic systems have been evaluated {preformed [(thf)W(CO)5], [W(CO)6]/excess Et3N, and [W(CO)6]/2 mol % Et3N]. We have found that the reaction proceeds to give the formal endo- or exo-cycloisomerization products depending on the amount of Et3N used and on the substitution along the alkyl chain of the starting alkynol. The theoretical study allowed us to find the mechanisms of the reactions which explain the formation of the formal endo- or exo-cycloisomerization products.
authors: Instituto Universitario de Química Organometálica, Enrique Moles, Unidad Asociada al CSIC, Universidad de Oviedo, Julián Clavería 8, 33006 Oviedo, Spain. barluenga@uniovi.es
authors: José
authors: J
authors: Barluenga
authors: Alejandro
authors: A
authors: Diéguez
authors: Félix
authors: F
authors: Rodríguez
authors: Francisco J
authors: FJ
authors: Fañanás
authors: Tomás
authors: T
authors: Sordo
authors: Pablo
authors: P
authors: Campomanes
mesh_terms: D002384:Catalysis; D003500:Cyclization; D004563:Electrochemistry; D009682:Magnetic Resonance Spectroscopy; D008962:Models, Theoretical; D013056:Spectrophotometry, Ultraviolet; D017973:Tungsten Compounds / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D017973:Tungsten Compounds