title: Functionalized N-heterocyclic carbene nonspectator ligands upon internal alkyne activation reactions.
abstract: When studying the activation of 3-arylpropiolates by [TpRu(picolyl-(R)I)Cl]/NaBAr(F)4 (picolyl-(Me)I = 3-methyl-1-(2-picolyl)imidazol-2-ylidene (1); picolyl-(Me)BI = 3-methyl-1-(2-picolyl)benzoimidazol-2-ylidene (2)) a migratory insertion of the NHC into a ruthenium-carbon bond and an unprecedented C-N bond activation of the chelating picolyl-NHC ligand take place to give the new ruthenium metallacycles [TpRu(κ(3)-C,N,N'-═C(Ph)-C(CH2Py)(CO2Me)((Me)I)][BAr(F)4] 3a and 4a and [TpRu(κ(3)-C,N,N'-═C(4-CF3Ph)-C(CH2Py)(CO2Me)((Me)I)][BAr(F)4] 3b and 4b. X-ray crystal structures of 3a and 3b are reported, and a mechanistic pathway is proposed. In contrast, activation of internal alkynones by a mixture of [TpRu(picolyl-(Me)I)Cl] complex (1) and NaBAr(F)4 led to isolation and characterization of the corresponding disubstituted vinylidene complexes. Also, structures of [TpRu(picolyl-(Me)I)(═CC(COR)(Ph)][BAr(F)4] (R = Me (6a); Ph (6b)) are reported.
authors.affiliation: Departamento de Ciencia de los Materiales e Ingeniería Metalúrgica y Química Inorgánica, Facultad de Ciencias, Universidad de Cádiz, 11510 Puerto Real, Cádiz, Spain.
authors.forename: Francys E
authors.initials: FE
authors.lastname: Fernández
authors.forename: María del Carmen
authors.initials: Mdel C
authors.lastname: Puerta
authors.forename: Pedro
authors.initials: P
authors.lastname: Valerga
mesh_terms: D000480:Alkynes / Q000737:chemistry*; D018360:Crystallography, X-Ray; D006571:Heterocyclic Compounds / Q000737:chemistry*; D008024:Ligands; D008697:Methane / Q000031:analogs & derivatives* / Q000737:chemistry; D008958:Models, Molecular; D008968:Molecular Conformation; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D012428:Ruthenium / Q000737:chemistry*
chemical_list: D000480:Alkynes; D006571:Heterocyclic Compounds; D008024:Ligands; D009942:Organometallic Compounds; C030011:carbene; D012428:Ruthenium; D008697:Methane