133779-04-1Relevant articles and documents
Redistribution at silicon by ruthenium complexes. Bonding mode of the bridging silanes in Ru2H4(μ-η2:η2:η2 :η2-SiH4)(PCy3)4 and Ru2H2(μ-η2:η2- H2Si(OMe)2)3(PCy3)2
Said, Ridha Ben,Hussein, Khansaa,Barthelat, Jean-Claude,Atheaux, Isabelle,Sabo-Etienne, Sylviane,Grellier, Mary,Donnadieu, Bruno,Chaudret, Bruno
, p. 4139 - 4146 (2003)
The bis(dihydrogen) complex RuH2(η2-H2)2 (PCy3)2 (1) reacts with 2 equiv. of H2SiMePh to produce a mixture of Ru2H4 (μ-η2:η2:η2:η2- SiH4)(PCy3)4 (2) and RuH2(η2-H2)(η2- HSiPh3)(PCy3)2 (4) together with HSiMePh2, HSiMe2Ph and traces of HMe2SiSiMe2H as a result of redistribution at silicon. The bridging SiH4 ligand in 2 is coordinated to the two ruthenium via four σ-Si-H bonds in agreement with NMR, X-ray data (on 2, and 2′ the analogous PiPr3 complex) and DFT calculations. Each interaction involves σ-donation to a ruthenium and back-bonding from the other ruthenium. Elimination of SiH4 and formation of RuH2(CO)2(PCy3)2 (5), RuH2(tBuNC)2(PCy3)2 (6) or RuH(η2-H2)Cl(PCy3)2 (7) were observed upon the reaction of 2 with CO, tBuNC, CH2Cl2, respectively. No reaction occurred in the presence of H2, but H/D exchange was observed under D2 atmosphere. Another redistribution reaction at silicon can be obtained by adding 4 equiv. of HSi(OMe)3 to 2 to produce Si(OMe)4 and Ru2H2(μ-η2:η2- H2Si(OMe)2)3(PCy3)2 (3) displaying three bridging (μ-η2:η2 alkoxysilane) ligands. Complex 3 is characterized by multinuclear NMR spectroscopies and by a crystal structure. DFT calculations show that the model complex Ru2H2(μ-η2:η2- H2Si(OR)2)3(PR3)2 (R = H, Me) is a minimum on the potential energy surface, and support the dihydride formulation with three bridging H2Si(OMe)2 ligands coordinated to the two ruthenium through σ-Si-H bonds.
ROMP using heterocyclic carbenes bearing a hydride ligand. An improved synthesis of RuCl2 (PR3)2(=CHMe)
Coalter III,Caulton
, p. 679 - 684 (2001)
The cyclic, heteroatom-stabilized carbene complexes RuHCl(PR3)2[=C(X)C3H6] (R = Pri, Cy; X = O, NH) catalyze the ring-opening metathesis polymerization of 2-norbornene to give mainly (85%) trans-polynorbornene (Mw 1.1-2.0 × 105 g mol-1) in arene solvent at 30-80 °C. Initiation is slow, but not dependent on free phosphine concentration because the catalyst has an empty coordination site cis to the carbene. Protonation of RuHCl(PR3)2[=C(OR)R'] species occurs at the hydride ligand, and the acidity of the resulting species leads to C-OR bond cleavage. This leads to facile conversion of RuHClL2[C(OEt)Me] to RuHCl2L2[=CHMe] and EtOH by HCl and, thus, a convenient new synthesis of a traditional metathesis catalyst whose carbene source is H2C=C(OEt)H.
Hydrogenolysis versus methanolysis of first-and second-generation grubbs catalysts: Rates, speciation, and implications for tandem catalysis
Beach, Nicholas J.,Camm, Kenneth D.,Fogg, Deryn E.
, p. 5450 - 5455 (2010)
An unexpected "generation gap" is uncovered between the Grubbs catalysts RuCl2(L)(PCy3)(=CHPh) (1a, L = PCy3; 1b, L = IMes, N,N′-bis(mesityl)imidazol-2-ylidene) in their reactions with hydrogen versus methanol, in the pres
Insights into the decomposition of olefin metathesis precatalysts
Manzini, Simone,Poater, Albert,Nelson, David J.,Cavallo, Luigi,Slawin, Alexandra M. Z.,Nolan, Steven P.
supporting information, p. 8995 - 8999 (2014/12/10)
The decomposition of a series of benzylidene, methylidene, and 3-phenylindenylidene complexes has been probed in alcohol solution in the presence of base. Tricyclohexylphosphane-containing precatalysts are shown to yield [RuCl(H)(H2)(PCy3)2] in isopropyl alcohol solutions, while 3-phenylindenylidene complexes lead to η5-(3- phenyl)indenyl products. The potential-energy surfaces for the formation of the latter species have been probed using density functional theory studies.
METHODS FOR PREPARING RUTHENIUM CARBENE COMPLEXES AND PRECURSORS THERETO
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Paragraph 0094, (2014/06/23)
Methods of preparing ruthenium carbene complex precursors are disclosed herein. In some embodiments, the methods include reacting a ruthenium refinery salt with an L-type ligand and a reducing agent to form the ruthenium carbene complex precursor. Methods of preparing a ruthenium vinylcarbene complex are also disclosed. In some embodiments, preparing a ruthenium carbene complex includes converting a ruthenium carbene complex precursor into a ruthenium carbene complex having a structure (PR1R2R3)2Cl2Ru═CH—R4, wherein R1, R2, R3, and R4 are defined herein.
Carbonyl-amplified catalyst performance: Balancing stability against activity for five-coordinate ruthenium hydride and hydridocarbonyl catalysts
Beach, Nicholas J.,Blacquiere, Johanna M.,Drouin, Samantha D.,Fogg, Deryn E.
, p. 441 - 447 (2009/05/30)
The activity of RuHCl(H2)(PCy3)(L) 2a/b and RuHCl(CO)(PCy3)(L) 3a/b (a: L = PCy3; b: L = IMes; IMes = 1,3-dimesitylimidazol-2-ylidene) was assessed in hydrogenation of a range of molecular and polymeric olefins
Activation of chlorosilanes at ruthenium: A route to silyl σ-dihydrogen complexes
Lachaize, Sebastien,Caballero, Ana,Vendier, Laure,Sabo-Etienne, Sylviane
, p. 3713 - 3721 (2008/10/09)
The hydrido σ-dihydrogen complex RuClH(η2-H 2)(PCy3)2 (2) reacts with the chlorosilanes HSiMe3-nCln (n = 1-3) to form the corresponding silyl σ-dihydrogen complexes RuCl(SiMe3-nCln) (η2-H2)(PCy3)2 (3Me 3-nCln). These complexes display a 16-electron configuration, as shown by NMR, by X-ray data in the case of 3MeCl2, and by theoretical calculations. The σ-H2 ligand in 3MeCl 2 has been located by X-ray diffraction, and the H-H distance of 1.05(3) A compares well with the value obtained by DFT/ B3PW91 (1.073 A) as well as with the value of 1.08 ± 0.01 A derived from the measurement of the JHD coupling constant of 17.5 Hz for the deuterated isotopomer RuCl(SiMeCl2)(η2-HD)(PCy 3)2. The series of model complexes RuCl(SiMe 3-nCln)(η2-H2)(PMe 3)2 (S3Me3-nCln) was investigated by DFT at the B3PW91 level. The most stable isomers have a structure that resembles the X-ray structure of 3MeCl2: i.e., a silyl σ-dihydrogen formulation. In the case of S3Me2Cl and S3MeCl2 a second minimum very close in energy was optimized and formulated as a hydrido σ-silane species. The influence of the number of Cl substituents on Si and their location have been analyzed. The difference between 3Me2Cl on one side and 3MeCl2 and 3Cl3 on the other side is highlighted both by NMR and DFT data and by their reactivity toward ethylene. No reaction was observed for the latter complexes, whereas reaction with 3Me2Cl produces the hydrido η2-ethylene complex RuClH(C2H4)(PCy 3)2 (4). In the case of styrene, the arene complex RuCl(SiMe2Cl)(η6-C8H10)(PCy 3) (5) was isolated.
Preparation of trifluorophosphaneruthenium(II) complexes from η3:η3-cyclooctadienediylruthenium(IV) compounds as precursors
Werner, Helmut,Stueer, Wolfram,Jung, Stefan,Weberndoerfer, Birgit,Wolf, Justin
, p. 1076 - 1080 (2007/10/03)
The dinuclear cyclooctadienediylruthenium(IV) compound [{RuCl2(η3:η 3-C10H16)}2] (1) reacts with PCy3 in 2-propanol under an H2 atmosphere to give the hydrido(dihydrog
Hydrogenolysis of a ruthenium carbene complex to yield dihydride-dihydrogen tautomers: Mechanistic implications for tandem ROMP-hydrogenation catalysis
Drouin,Yap,Fogg
, p. 5412 - 5414 (2008/10/08)
Conversion of Grubbs's catalyst 1 into a hydrogenation catalyst is described. Hydrogenolysis of the Rucarbene bond in CH2Cl2 yields Ru(IV) species 2; in other solvents, a mixture of 2 and its dihydrogen tautomer 4 is formed, even in the presence of base. Further reaction gives hydridochloro complex RuHCl(H2)(PCy3)2 3, which reverts to 2 in CH2Cl2.
Reactivity of Ru(H)(H2)Cl(PCy3)2 with propargyl and vinyl chlorides: New methodology to give metathesis-active ruthenium carbenes
Wilhelm, Thomas E.,Belderrain, Tomás R.,Brown, Seth N.,Grubbs, Robert H.
, p. 3867 - 3869 (2008/10/08)
A procedure for generating the ruthenium hydride complex Ru(H)(H2)Cl(PCy3)2 in 95% yield is presented. Following a novel insertion - elimination pathway, this hydride can react with propargyl or vinyl halides to make metathesis-active vinyl and alkyl carbene species with the general formulas (PCy3)2Cl2-Ru=CH-CH=CR2 and (PCy3)2Cl2Ru=CHR, respectively. Tertiary propargyl chlorides work best, giving Ru-vinyl carbenes in extremely high yield.
