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Related Reaction (relate + reaction)
Selected AbstractsSynthesis and Structure of Two New High Nuclearity Ru/Pt Mixed-Metal ClustersEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 7 2003Brian F. G. Johnson Abstract The reaction of the dianion [Ru5C(CO)14]2, with [PtCl2(MeCN)2] in the presence of silica yields [Ru5PtC(CO)16] (1) and the new compound [PPN]2[Ru10Pt2C2(CO)28] (2), while, in a related reaction, [Ru6C(CO)16]2, undergoes addition of [PtCl2(MeCN)2] to yield the cluster [Ru12PtC2(CO)32(MeCN)2] (3). The high nuclearity compounds 2 and 3 have been fully characterized and their structures determined by single crystal X-ray analysis. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003) [source] The emitting species formed by the oxidation of hydrazides with hypohalites or N-halosuccinimidesLUMINESCENCE: THE JOURNAL OF BIOLOGICAL AND CHEMICAL LUMINESCENCE, Issue 4 2004Paul S. Francis Abstract The chemiluminescence accompanying the oxidation of salicylic hydrazide (2-hydroxybenzoic acid hydrazide) with hypochlorite, hypobromite, N-chlorosuccinimide, N-bromosuccinimide or hydrogen peroxide with cobalt(II) matched the photoluminescence emission of salicylic acid. In a related reaction, the oxidation of a mixture of isoniazid and ammonia, a synergistic effect was observed. The chemiluminescence spectrum for this reaction matches that accompanying the oxidation of the hydrazide, rather than the oxidation of ammonia. These results were used to assess mechanisms proposed by previous authors. Copyright © 2004 John Wiley & Sons, Ltd. [source] Application of the 1,3-Dipolar Cycloaddition Reaction in Chemical Biology: Approaches Toward Multivalent Carbohydrates and Peptides and Peptide-Based PolymersMOLECULAR INFORMATICS, Issue 11-12 2007Roland Abstract In this mini review we highlight our recent results and the related literature regarding the application of the Cu(I)-catalyzed 1,3-dipolar cycloaddition "click" reaction. The synthetic applications of the click reaction focus on multivalent carbohydrates and peptides and peptide-based polymers. Furthermore, a related reaction is described involving the coupling of thio acids and sulfonyl azides leading to the chemoselective formation of amides. [source] Synthesis and Characterisation of ,3 -Octahedral [Ni36Pd8(CO)48]6, and [Ni35Pt9(CO)48]6, Clusters Displaying Unexpected Surface Segregation of Pt Atoms and Molecular and/or Crystal Substitutional Ni/Pd and Ni/Pt DisorderCHEMISTRY - A EUROPEAN JOURNAL, Issue 9 2004Cristina Femoni Dr. Abstract The synthesis and structure, as well as the chemical and electrochemical characterisation of two new ,3 -octahedral bimetallic clusters with the general [Ni44,xMx(CO)48]6, (M = Pd, x = 8; M = Pt, x = 9) formula is reported. The [Ni35Pt9(CO)48]6, cluster was obtained in reasonable yields (56,% based on Pt) by reaction of [Ni6(CO)12]2, with 1.1 equivalents of PtII complexes, in ethyl acetate or THF as the solvent. The [Ni36Pd8(CO)48]6, cluster was obtained from the related reaction with PdII salts in THF, and was isolated only in low yields (5,10,% based on Pd), mainly because of insufficient differential solubility of its salts. The unit cell of the [NBu4]6[Ni35Pt9(CO)48] salt contains a substitutionally Ni,Pt disordered [Ni24(Ni14,xPtx)Pt6(CO)48]6, (x = 3) hexaanion. A combination of crystal and molecular disorder is necessary to explain the disordering observed for the Ni/Pt sites. The unit cell of the corresponding [Ni36Pd8(CO)48]6, salt contains two independent [Ni30(Ni8,xPdx)Pd6(CO)48]6, (x = 2) hexaanions. The two display similar substitutional Ni,Pd disorder, which probably arises only from crystal disorder. The structure of [Ni36Pd8(CO)48]6, establishes the first similarity between the chemistry of Ni-Pd and Ni-Pt carbonyl clusters. A comparison of the chemical and electrochemical properties of [Ni35Pt9(CO)48]6, with those of the related [Ni38Pt6(CO)48]6, cluster shows that surface colouring of the latter with Pt atoms decreases redox as well as protonation propensity of the cluster. In contrast, substitution of all internal Pt and two surface Ni with Pd atoms preserves the protonation behaviour and is only detrimental with respect to its redox aptitude. A qualitative rationalisation of the different surface-site selectivity of Pt and Pd, based on distinctive interplays of MM and MCO bond energies, is suggested. [source] Imidazol(in)ium-2-carboxylates as N-Heterocyclic Carbene Precursors for the Synthesis of Second Generation Ruthenium Metathesis CatalystsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 11-12 2009Xavier Sauvage Abstract Five well-known ruthenium-N-heterocyclic carbene (NHC) catalysts for olefin metathesis and related reactions, including the second generation Grubbs and Hoveyda,Grubbs catalysts, were prepared by phosphane exchange between first generation ruthenium-benzylidene or indenylidene complexes and NHCs generated in situ upon thermolysis of imidazol(in)ium-2-carboxylates. Because N-heterocyclic carbene carbon dioxide adducts (NHC,CO2) are stable zwitterionic compounds that can be stored and handled with no particular precautions, this procedure is particularly attractive from a practical point of view. Reaction courses were conveniently monitored by 31P,NMR spectroscopy and the experimental conditions were carefully adjusted to obtain high yields of pure products within short periods of time. [source] Michael Polanyi and the discovery of co-catalysis: Discussion of an autobiographical letter from Michael Polanyi, FRS to Peter H. Plesch of 17 December 1963JOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 7 2004P. H. Plesch Abstract The origin of this memoir was a letter from Michael Polanyi (M. P.) to the present writer (P. H. P.) about their researches in the mid-1940s into the mechanism of what are now called cationic polymerizations, at the University of Manchester (England). M. P. analyzes his tactics and the mistakes made in directing this research. When the Manchester-trained researchers made little progress with what was a very recalcitrant problem, M. P. thinking that scientists from a different background might be more sucessful, got P. H. P., from Cambridge, to work with an Oxford-trained chemist. They recognized that the likely cause of the irreproducibility of these polymerizations was the apparatus used which permitted access of atmospheric moisture to the reaction mixtures containing the moisture-sensitive catalytic metal halides. Because the only method for following the very fast polymerizations was by monitoring the accompanying temperature rise, and the reactions had to be done below ambient temperature, the reaction vessel needed to be adiabatic, that is a Dewar (Thermos) flask; hence the problem of how to cool its contents. The solution was P. H. P.'s invention of the pseudo-Dewar vessel, the Dewar space of which, instead of being evacuated permanently, could be filled with air or evacuated. This device permitted the reaction mixture to be made up and cooled, and the reactions to be started without contact with the atmosphere. Thus it was found that isobutene polymerizations, which had stopped unaccountably, could be restarted by water vapor. P. H. P. termed water a "co-catalyst". The consequent "Manchester" theory recognized the monohydrate of TiCl4 as a protonic acid and saw the initiation as due to the protonation of the monomer, with the formation of a tert -carbenium ion, and these ions, formed repetitively, became the propagating species. The Manchester theory was rapidly accepted because it could also explain observations on other related reactions. The involvement of ions established a link with non-aqueous electrochemistry. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 1537,1546, 2004 [source] | ||||||||||