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Organo-metallic chelates

Stereoselective addition to an a-alkoxy aldehyde.3 The addition of organo-metallic reagents to acrolein dimer 1 can be controlled to a remarkable extent by the metal, evidently as a result of chelation, with R2Zn being more stereoselective than RLi or RMgBr. [Pg.221]

Our third contribution is by Alexander Sadimenko, of the University of Fort Hare, (Republic of South Africa) and continues the series of organo-metallic complexes of heterocycles. The present contribution covers a broad class of chelating ligands constituted by phosphinopyridines and related compounds. These interesting ligands possess both hard (pyridine nitrogen) and soft (phosphorus) coordination sites, which provides them with special properties in coordination chemistry. [Pg.508]

GC has been used extensively for the separation and determination of volatile organic molecules, and most aspects of this application area are fully documented in monographs on this technique. In the inorganic trace analysis area, however, fewer species possess the required volatility, and applications tend to be limited to the separation of volatile species of low molecular weight (such as methyl derivatives of As, Se, Sn, Hg) and the separation of semi-volatile organo-metals, metal halides, metal hydrides, metal carbonyls and metal chelates. For organo-metal species, the type of detection system required varies with the nature of the analyte, and the options include electron capture detection, flame photometric detection (sometimes ICP), AAS and MS. [Pg.19]

Excellent reviews on colloidal solutions, halogenation, alkylation, saponification, sulfonation, organo-metallic compounds Plastics, irradiation, copolymerization, chelates, ion exchange, etc. [Pg.237]

Chelating phosphines see Coordination Organo-metallic Chemistry Principlei) have interesting effects on hydroformylation. R2P(CH2)xPR2 (x = 2-4) ligands with... [Pg.665]

The recent extension of these thermodynamic models to include the kinetics and mechanisms of organo-metallic interactions has made it possible (1) to quantify the electrochemical availability of these metal complexes to voltammetric systems (Whitfield and Turner, 1980) (2) to examine diffusion and dissociation models for the tremsport of chelated iron to biological cells (Jackson and Morgan, 1978) and (3) to estimate the significance of adsorptive and convective removal processes on the equilibrium specia-tion of metals in natural waters (Lehrman and Childs, 1973). Thus both equOibrium and dynamic models have become an indispensable tool in the identification of the important chemical forms and critical reaction pathways of interactive elements in aquatic environments. [Pg.212]

Cheluviation. Cheluviation involves the transport of organo-metallic complexes (i.e., chelates) of iron and aluminum. Once transported to the lower horizon B, the iron and aluminum precipitate as iron and aluminum sesquioxides forming colored spodic horizons denoted B,. [Pg.930]

A review on the industrial applications of homogeneous catalysts is particularly welcome. The proceedings of recent symposia and a general text have been published in addition to reviews on metal cluster catalysts, activation of saturated hydrocarbons by metal complexes in solution, catalysis by arene Group-VIB tricarbonyls, titanocene-catalysed reactions ofalkenes, transition-metal hydrides in catalysis, the mechanisms of the catalytic cyclization of aliphatic, hydrocarbons, asymmetric hydrosilylation and asymmetric synthesis. A n.m.r. study of the conformations of chelated Diop and a MO study of organo-metallic migration reactions are also of interest. Polymer supported catalysts have been reviewed and the relationship between cross-linking of the polymer and catalytic activity has been discussed. ... [Pg.400]

In an example that shows the strong donor character of NHCs, the tripodal polydentate NHC ligand in 11.26 stabilizes Fe(V) as an organo-metallic nitride. Not all potentially chelating bis-NHC ligands in fact form chelates, however, even when the chelate would be thermodynamically favored. Each NHC often binds to a separate metal in a 2 1 complex as kinetic product because, unlike M-PR3, M-NHC bond formation is not reversible, so the error cannot be remedied by reversible dissociation (Eq. 11.42). [Pg.309]


See other pages where Organo-metallic chelates is mentioned: [Pg.243]    [Pg.22]    [Pg.375]    [Pg.58]    [Pg.18]    [Pg.226]    [Pg.185]    [Pg.58]    [Pg.168]    [Pg.359]    [Pg.359]    [Pg.35]    [Pg.416]    [Pg.996]    [Pg.499]    [Pg.180]    [Pg.88]    [Pg.252]    [Pg.307]    [Pg.365]    [Pg.359]    [Pg.69]    [Pg.163]    [Pg.33]    [Pg.110]    [Pg.455]    [Pg.323]    [Pg.463]    [Pg.58]    [Pg.552]    [Pg.221]    [Pg.106]    [Pg.153]    [Pg.86]    [Pg.121]    [Pg.117]    [Pg.119]   
See also in sourсe #XX -- [ Pg.416 ]




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Metal chelates

Metal chelating

Metal chelation

Metal chelator

Metal chelators

Organo-metals

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