1529-27-7Relevant academic research and scientific papers
The Identity in Atomic Structure and Performance of Active Sites in Heterogeneous and Homogeneous, Titanium-Silica Epoxidation Catalysts
Thomas, John Meurig,Sankar, Gopinathan,Klunduk, Marek C.,Attfield, Martin P.,Maschmeyer, Thomas,Johnson, Brian F. G.,Bell, Robert G.
, p. 8809 - 8813 (1999)
The nature of the Ti(IV) active site in heterogeneous titano-silica epoxidation catalysts is shown to be same as that of a Ti(IV)-centered site bound to soluble homogeneous silsesquioxane catalysts. A range of techniques, encompassing pre- and near-edge X-ray absorption spectroscopy and molecular dynamics calculations, provides quantitative information pertaining to the four-coordinated site that is tripodally anchored to silica. The catalytic performance of a series of engineered active sites in [(c-C5H9)7Si7O 12TiOXPh3], where X = Si, Ge, or Sn, shows that the order of enhancement is Ge > Sn > Si. This is compared with previously published7 performances of engineered active sites in solid titano-silicate catalysts. The key importance of accessibility to the four-coordinated Ti(IV) site is highlighted here.
Complexes containing bridging tin- and germanium-substituted metallocarboxylate ligands from the reactions of Ph3SnOH and Ph 3GeOH with Os3(CO)12 in the presence of base
Adams, Richard D.,Chen, Mingwei,Trufan, Eszter
, p. 2894 - 2898 (2011)
The first examples of bridging tin- and germanium-substituted metallocarboxylate ligands have been obtained from the reactions of Ph 3SnOH and Ph3GeOH with Os3(CO)12 under basic conditions. Two products: Os
THE CHEMICAL BEHAVIOUR OF COBALT-STABILIZED-CARBENES HAVING A TRISUBSTITUTED SILYL OR GERMYL LIGAND. STEREOSPECIFIC FORMATION OF BENZOYLSILANES FROM THE REACTION OF ORGANOSILYL-COBALT TETRACARBONYL DERIVATIVES WITH PHENYLLITHIUM
Cerveau, Genevieve,Colomer, Ernesto,Corriu, Robert J.P.,Young, J. Colin
, p. 31 - 45 (2007/10/02)
We report the chemical behaviour of cobalt-stabilized carbenes, R3M(CO)3CoC(OEt)R', and their parent anions, R3M(CO)3CoC(O-)R', where M = Si or Ge.The anions where M = Si, R' = Ph decompose thermally into the corresponding benzoylsilanes; when the silicon atom is chiral (R3 = MePh-1-Np) optically active R3SiCOPh is obtained with complete retention of configuration.
ELECTROCHEMICAL REDUCTION OF TRIORGANOHALO-SILANES AND -GERMANES
Corriu, R. J. P.,Dabosi, G.,Martineau, M.
, p. 63 - 72 (2007/10/02)
The electrochemical reduction of triorganohalo-silanes and -germanes in 1,2-dimethoxyethane has been investigated by polarography, cyclic voltammetry, controlled potential coulometry, and macroscale electrolysis.The reduction of the silicon compounds exhibits a single irreversible wave.The polarograms for the germanium compounds exhibit two irreversible waves.The second wave shifts to more anodic potentials with addition of phenol or acetic acid.Dimer (i.e. disilanes or digermanes) are the main product of macroscale electrolysis in aprotic solvent but the hydrides are the principal products in protic solution.The results are interpreted in terms of the coexistence of two separate processes.The first involves a one electron reduction followed by dimerization of the radical.At higher cathodic potential a two electron charge transfer step occurs to form an anion, which in aprotic solvents reacts with the starting halogeno compound to form dimer, and in protic solutions gives the hydride.
