104 research outputs found
CD80 down-regulation is associated to aberrant DNA methylation in non-inflammatory colon carcinogenesis
Nichel (0) complexes with the hybrid bidentate ligand 1-(thioethyl)-2-(diphenylphosphino)ethane. Syntesis and catalytic properties of the related nickel hydride derivative
Reductive Carbonylation of Phosphine-Complexes of Cobalt(II). A Kinetic Investigation
The stoichiometry and kinetics of the reaction of carbon monoxide with [CoI2(CO)(PEt3)2] were examined in different solvents and in the presence of free PEt3. The results are interpreted in terms of a mechanism in which an iodide-bridged dicobalt species undergoes carbon monoxide addition to give an intermediate which is reduced by external PEt3. © 1982
Reductive carbonylation of Phosphino-complexes of cobalt(II), a kinetic investigation
The stoichiometry and kinetics of the reaction of carbon monoxide with [CoI2(CO)(PEt3)2] were examined in different solvents and in the presence of free PEt3. The results are interpreted in terms of a mechanism in which an iodide-bridged dicobalt species undergoes carbon monoxide addition to give an intermediate which is reduced by external PEt3. © 1982
Solventless silane alcoholysis catalyzed by recoverable dirhodium(II) perfluorocarboxylates
We have developed a novel reaction protocol for the highly efficient and sustainable catalysis of the silane alcoholysis reaction. The catalysts of choice are dirhodium(II) perfluorocarboxylates bearing long perfluoroalkyl chains, which are easily prepared in one step from commercial precursors. Under optimized reaction conditions, these catalysts exhibit up to about 50 times higher activity and 100 times higher productivity than analogous dirhodium(II) complexes described in the prior art. Furthermore, the reaction can be run in a completely solventless fashion. Finally, heterogenization of these catalysts has been accomplished through a novel strategy based on fluorous chemistry. Indeed, perfluorinated catalysts of this kind are easily adsorbed on silica which has been previously functionalized at its surface with perfluoroalkyl chains. Use of such supported catalysts (bonded fluorous phase catalysts) allows an easy and almost complete catalyst separation and recycling with improved catalytic performance
Nickel(0) complexes with the hybrid bidentate ligand 1-(thioethyl)-2-(diphenylphosphino)ethane. Synthesis and catalytic properties of the related nickel hydride derivative
Metal-catalysed carbon-carbon bond formation in the reaction of malononitrile with beta-dicarbonyls
Nickel acetylacetonate effectively catalyses the carbon-carbon bond formation between malononitrile and beta-dicarbonyls. In these metal-catalysed reactions malononitrile behaves as an electrophile towards the intercarbonylic carbon, so exhibiting a reverse reactivity compared with that one under basic or thermal conditions. The resulting organic products are beta-cyanomethylene-beta-enamino dicarbonyls (2a-h), which are obtained in good-to fair yield. beta-Iminodicarbonyl complexes of nickel(II) and copper(II), which are likely intermediates in the catalytic cycle, are synthesised by reaction of the metal beta-carbonylenolate with malononitrile or of the metal acetate with the catalysis product (2a, d)
Reactivity of cyanogen towards compounds containing active hydrogens at carbon. 6. Addition to \u3b2-dicarbonylenolato complexes of nickel(II) and ligand ability of bis[1-cyano-2-(1-iminoethyl)butane-1,3-dionate]nickel(II) towards PdCl 2
The bis-[\u3b2-carbonylenolato)nickel(II) complexes [Ni(eaa) 2] (eaa = ethylacetoacetato), [Ni(ba) 2] (ba = benzoylacetonato), [Ni(dbm) 2] (dbm = dibenzoylmethanato), [Ni(dpm) 2] (dpm = dipavaloylmethanato) are found to be reactive towards C 2N 2 to give selectively square-planar complexes of stoichiometry [Ni(ligand\ub7C 2N 2) 2]. The reaction of [Ni(acac) 2] with C 2N 2 was re-considered and the nature of two supposed isomeric products has been thoroughly reinvestigated by a variety of physico-chemical methods, including a combination of thermogravimetry-differential thermal analyses. The complex [Ni\u3b2 2] (\u3b2 = 1-cyano-2-(1-iminoethyl)butane-1,3-dionate) reacts quantitatively with [PdCl 2(PhCN) 2] to give a coordination polymer of approximate composition [(PdCl 2)(Ni\u3b2 2) 0.25]. \ua9 1984
“ Reactivity of [Pd3(μ-O2CMe)3(μ-MeSCHC(O)OR)3] (R= Me, Et) towards bidentate nucleophiles: X-ray structure of [Pd2(acac)2(μ-MeSCHC(O)OEt)2]”
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