371234-06-9Relevant academic research and scientific papers
Simultaneous observation of doubly and triply chloride bridged isomers of an electron-rich ruthenium dimer: Role of dimer geometry in determining reactivity
Drouin, Samantha D.,Monfette, Sebastien,Amoroso, Dino,Yap, Glenn P.A.,Fogg, Deryn E.
, p. 4721 - 4728 (2008/10/09)
High-yield routes to the dimeric monocarbonyl complexes [RuCl 2(PP)(CO)]2 (3; PP = dcypb, 1,4-bis(dicyclohexylphosphino) butane) are established via (a) decarbonylation of mononuclear RuCl 2(PP)(CO)2 (4), (b) one-pot carbonylation-decarbonylation of RuCl(PP)(μ-Cl)3Ru(PP)(N2) (1), and, most conveniently, (c) phosphine exchange of RuCl2(PPh3) 3 with dcypb, followed by a carbonylation-decarbonylation sequence as in (b), all three steps being carried out in a one-pot procedure. One or three isomers of 3 can be observed by NMR analysis, depending on the solvent medium. A mixture of [RuCl(PP)(CO)]2(μ-Cl)2 (transoid, 3a; cisoid, 3b) and ionic {[Ru(PP)(CO)]2(μ-Cl)3}Cl (3c) is present in benzene, chlorobenzene, or THF. In CH2Cl2 or CDCl3, only 3c is observed. This represents the first Ru 2X4L4 system (L = L, L′) in which three of the possible edge-bridging and face-bridging isomers can be simultaneously observed and in which their ratio can be manipulated. Reactivity studies indicate that the face-sharing isomer 3c is considerably more stable than its edge-sharing isomers. Transformations of 3 are significantly accelerated by introduction of a donor solvent (methanol, THF). Product identities were established by 1H, 13C, and 31P NMR and IR spectroscopy, by microanalysis, and by X-ray crystallography (3a/3b, 3c, 4a/4b).
Compatibility of the vinylidene ligand and perfluorophenoxide
Drouin, Samantha D.,Foucault, Heather M.,Yap, Glenn P.A.,Fogg, Deryn E.
, p. 2583 - 2590 (2008/10/09)
The stability of the Ru-vinylidene moiety toward instatllation of a perfluorophenoxide ligand was investigated. Mononuclear complex, containig four nonlabile ligands cis to the vinylidene moiety, was found to be unreactive until it was activated by protonolysis of arlyoxide. The product identities were established by 1H, 13C, and 31P NMR and IR spectroscopy, and x-ray crystallography. The results show that the high thermodynamic stability of the ruthenium complex entity, other two complexes exhibited low activity in ring-opening metathesis polymerization of norbornene.
The life, death, and ROMP activity of ruthenium complexes containing the basic, chelating diphosphine bis(dicyclohexyl)-1,4-phosphinobutane
Amoroso,Yap,Fogg
, p. 958 - 963 (2007/10/03)
Reaction of RuCl2(PPh3)3 with bis(dicyclohexyl)-1,4-phosphinobutane (dcypb) under N2 affords access to a formerly elusive family of dcypb complexes based on the RuCl2(PP) core. Under Ar or vacuum atmosphere, decomposition occurs via Ru-promoted dehydrogenation of the dcypb ligand. While the N2-stabilized species [RuCl2(dcypb)]2(N2) (4a) is easily handled under N2 in nonchlorinated solvents, reaction with chlorinated solvents rapidly yields paramagnetic Ru2Cl5(dcypb)2 (5). The N2 ligand within 4a is readily displaced under H2 or CO atmosphere, yielding Ru2Cl4(dcypb)2(H2) (6) or RuCl2(dcypb)(CO)2, the latter as a mixture of ccc-(7) and tcc-(8) isomers. Benzylidene derivative RuCl2(dcypb)(CHPh) (1a), prepared in situ by reaction of 4a with PhCHN2, proves exceptionally active in ring-opening metathesis polymerization (ROMP) of norbornene. The X-ray crystal structure of 5 is reported: triclinic, a = 13.390(2), b = 15.726(2), c = 19.524(2) A, α = 77.325(2), β = 70.964(2), γ = 73.478(2)°, with space group P1 and Z = 2.
