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Coordination chemistry and

Halpern J, Riley D P, Chan A S C and Pluth J J 1977 Novel coordination chemistry and catalytic properties of cationic 1,2-bis(diphenylphosphino)ethanerhodium(l) complexes J. Am. Chem. Soo. 99 8055-7... [Pg.2713]

This thesis contributes to the knowledge of catalysis in water, us it describes an explorative journey in the, at the start of the research, unh odded field of catalysis of Diels-Alder reactions in aqueous media. The discussion will touch on organic chemistry, coordination chemistry and colloid chemistry, largely depending upon the physical-organic approach of structural variation for the elucidation of the underlying mechanisms and principles of the observed phenomena. [Pg.2]

Cobalt exists in the +2 or +3 valence states for the majority of its compounds and complexes. A multitude of complexes of the cobalt(III) ion [22541-63-5] exist, but few stable simple salts are known (2). Werner s discovery and detailed studies of the cobalt(III) ammine complexes contributed gready to modem coordination chemistry and understanding of ligand exchange (3). Octahedral stereochemistries are the most common for the cobalt(II) ion [22541-53-3] as well as for cobalt(III). Cobalt(II) forms numerous simple compounds and complexes, most of which are octahedral or tetrahedral in nature cobalt(II) forms more tetrahedral complexes than other transition-metal ions. Because of the small stabiUty difference between octahedral and tetrahedral complexes of cobalt(II), both can be found in equiUbrium for a number of complexes. Typically, octahedral cobalt(II) salts and complexes are pink to brownish red most of the tetrahedral Co(II) species are blue (see Coordination compounds). [Pg.377]

Compared to later elements in their respective transition series, scandium, yttrium and lanthanum have rather poorly developed coordination chemistries and form weaker coordinate bonds, lanthanum generally being even less inclined to form strong coordinate bonds than scandium. This is reflected in the stability constants of a number of relevant 1 1 metal-edta complexes ... [Pg.950]

Until comparatively recently only vanadium had a significant coordination chemistry and even so the majority of its compounds are easily oxidized and must be prepared with air rigorously excluded. The usual methods are to use VCI3 as the starting material, or to reduce solutions of vanadium(V) or (IV) electrolytically. However, the reduction of pentahalides of Nb and Ta by Na amalgam or Mg, has facilitated the expansion of Nb " and Ta " chemistry particularly with S-and P-donor ligands. [Pg.996]

Atropoisomeric binaphthalene-core phosphacyclic derivatives in coordination chemistry and homogeneous catalysis 97CB543. [Pg.270]

Chloroaluminate(III) ionic liquid systems are perhaps the best established and have been most extensively studied in the development of low-melting organic ionic liquids with particular emphasis on electrochemical and electrodeposition applications, transition metal coordination chemistry, and in applications as liquid Lewis acid catalysts in organic synthesis. Variable and tunable acidity, from basic through neutral to acidic, allows for some very subtle changes in transition metal coordination chemistry. The melting points of [EMIM]C1/A1C13 mixtures can be as low as -90 °C, and the upper liquid limit almost 300 °C [4, 6]. [Pg.43]

Distinctive coordination chemistry and biological significance of complexes with macrocyclic ligands. D. H. Busch, Acc. Chem. Res., 1978,11, 392-400 (61). [Pg.53]

Pauling, L. Herman, Z.S. Valence-Bond Concepts in Coordination Chemistry and the Nature of Metal-Metal Bonds J. Chem. Educ. 1984, 61, 582-587. [Pg.340]

Agbossou E., Carpentier J. E. Hapiot E., Suisse I., Mortreux A. The Aminophos-phine-Phosphinites and Related Ligands Synthesis, Coordination Chemistry and Enantioselective Catalysis Coord. Chem. Rev. 1998 I78-I80 1615-1645 Keywords stereoselective Diels-Alder reaction catalysts, aminophosphine-phosphinites, enantioselective catalysts... [Pg.307]

In particular, the study of SRB ferredoxins enables us to survey the different properties of simple iron-sulfur proteins, including electron transfer, flexibility in coordination chemistry, and ability to undergo cluster interconversions. Most of the observations can be extrapolated to more complex situations. [Pg.370]

The field of transition metal complexes of isocyanides developed slowly over more than a century to a respectable subarea in coordination chemistry, and in the process seems to have attracted very little attention. Even the remarkable resurgence of transition metal organometallic chemistry in the last 20 years, and the realization that isocyanides and carbon monoxide should be quite similar as ligand groups in organometallic complexes, did not initiate an extensive development of this area of chemistry. Only in the last several years has this potentially important subject begun to receive the attention it would seem to deserve. [Pg.21]

Synthesis, coordination chemistry and analytical uses of monothio-/3-diketones Sulphinato complexes... [Pg.513]

In the sixties of past century, a few patents issued to Bergbau Chemie [5,48,49] and to Mobil Oil [50-52], respectively described the use of CFPs as supports for catalytically active metal nanoclusters and as carriers for heterogenized metal complexes of catalytic relevance. For the latter catalysts the term hybrid phase catalysts later came into use [53,54], At that time coordination chemistry and organo-transition metal chemistry were in full development. Homogeneous transition metal catalysis was expected to grow in industrial relevance [54], but catalyst separation was generally a major problem for continuous processing. That is why the concept of hybrid catalysis became very popular in a short time [55]. [Pg.208]

Orbitally degenerate grormd states, in general, cannot be treated in the spin-Hamiltonian approach. In this case, SOC has to be evaluated explicitly on an extended basis of spin-orbit functions. However, in coordination chemistry and bioinorganic chemistry, this is only of marginal importance, because the metal centers of... [Pg.131]

The key role played by diverse nickel complexes in the development of C02 coordination chemistry and C02 electroreduction catalysts has been highlighted, 440 and several reviews discussing C02 electroreduction and photoreduction are available.2441-2445... [Pg.498]

This volume presents a survey of significant developments in the chemistry of Groups 7 and 8 of the transition metals since the publication of Comprehensive Coordination Chemistry (CCC) in 1987. The material for each element is organized by oxidation state of the metal and also by the nature of the ligands involved, with additional sections covering special features of the coordination chemistry and applications of the complexes. [Pg.1296]

Chen, X.M. and Tong, M.L. (2007) Solvothermal in situ metal/ligand reactions a new bridge between coordination chemistry and organic synthetic chemistry. Accounts of Chemical Research, 40 (2), 162—170. [Pg.79]

IV. Organosilicon Metal Compounds Coordination Chemistry and Catalysis... [Pg.8]

Indium and gallium coordination compounds containing phosphine ligands have recently aroused interest for their widespread application as intermediates in the preparation of the Group 13 - Group 14 semiconductors [4], Since the early reports about compounds with transition metal-indium bonds [51, relatively little research has been reported in this field. However there is a growing interest in the coordination chemistry and structural features of heterometallic indium [6] and gallium complexes [7] which are also attractive as potential precursors of new materials with particular properties. [Pg.200]

Some of the types of equilibria involved in the unit operations separation and concentration are listed in the introduction, Section 9.17.1. Those which depend most on coordination chemistry, and for which details of metal complex formation are best understood, are associated with hydrometallurgy. Once the metal values have been transferred to an aqueous solution, the separation from other metals and concentration can be achieved by one of the following processes.3... [Pg.768]


See other pages where Coordination chemistry and is mentioned: [Pg.1266]    [Pg.54]    [Pg.60]    [Pg.63]    [Pg.368]    [Pg.794]    [Pg.227]    [Pg.332]    [Pg.457]    [Pg.74]    [Pg.335]    [Pg.491]    [Pg.2]    [Pg.239]    [Pg.40]    [Pg.251]    [Pg.1149]    [Pg.1295]    [Pg.1296]    [Pg.75]    [Pg.90]    [Pg.152]    [Pg.157]    [Pg.164]    [Pg.169]    [Pg.169]    [Pg.827]   


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Coordination chemistry

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