459141-49-2Relevant academic research and scientific papers
Synthesis and characterization of 2-oxacycloalkylideneruthenium(II) complexes: X-ray crystal structure of the 2-oxacycloheptylidene complex [Ru{=COCH2(CH2)3CH2} (η5-C9H7) (PPh3)2] [PF6]·CH2Cl2
Gamasa, M.Pilar,Gimeno, José,Martín-Vaca, Blanca M.,Isea, Raúl,Vegas, Angel
, p. 22 - 33 (2002)
The oxacyclocarbene complexes [Ru{=COCH2(CH2)nCH2}(η 5-C9H7)LL′] [PF6]·(L = L′ = PPh3, n = 1 (2a), 2 (3a), (5a); L = L′ = PMe2Ph, n = 1 (2b), 2 (3b), 3 (5b); LL′ = dppm, n = 1 (2c), 2 (3c), 3 (5c); L = PPh3, L′ = PMe3, n = 1 (2d), 2 (3d), 3 (5d), have been prepared by reaction of [RuCl(η5-C9H7)LL′] with 3-butyn-1-ol, 4-pentyn-1-ol and 5-hexyn-1-ol in refluxing ethanol and in the presence of NaPF6. The process involves alkyne to vinylidene tautomerization to give hydroxyalkylvinylidene intermediate complexes. The vinylidene complexes [Ru{=C=C(H)(CH2)3CH2OH}(η5- C9H7)LL′][PF6 ] (L = L′ = PPh3 (4a), L = L′ = PMe2Ph (4 b), L = PPh3, L′ = PMe3 (4d) have been isolated from the reaction of [RuCl(η5-C9H7)LL′] with 5-hexyn-1-ol. The first structure for a 2-oxacycloheptylidene complex, 5a, has been determined by X-ray diffraction methods. The molecular structure shows the typical pseudooctahedral three-legged piano-stool geometry around the ruthenium atom, which is linked to the phosphorus atoms of the triphenylphosphine ligands and to the Cα of the oxacyclic carbene ligand; the coordination around the ruthenium atom is completed by a η-bonded indenyl ligand with the benzo ring orientated nearly trans to the carbene group (CA = 16.6(6)°). The Ru-Cl distance, 1.89(1) A?, is somewhat shorter than that found for other oxacyclic carbene ruthenium(II) complexes. The oxacycloheptylidene ring adopts a 'pseudochair' conformation for the seven member ring and shows an appreciable deviation from vertical orientation (DA = 29.7(5)°).
