Crystal-Field Theory
... Tetrahedral and Square-Planar Complexes • Square planar complexes can be thought of as follows: start with an octahedral complex and remove two ligands along the z-axis. • As a consequence the four planar ligands are drawn in towards the metal. • Relative to the octahedral field, the orbital is grea ...
... Tetrahedral and Square-Planar Complexes • Square planar complexes can be thought of as follows: start with an octahedral complex and remove two ligands along the z-axis. • As a consequence the four planar ligands are drawn in towards the metal. • Relative to the octahedral field, the orbital is grea ...
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... chemistry since carbonyl compounds are widely used as intermediates both in manufacturing and research [1]. Although the oxidation of organic compounds under non-aqueous conditions has become an effective technique for modern organic synthesis [2], the methods still suffer some disadvantages includi ...
... chemistry since carbonyl compounds are widely used as intermediates both in manufacturing and research [1]. Although the oxidation of organic compounds under non-aqueous conditions has become an effective technique for modern organic synthesis [2], the methods still suffer some disadvantages includi ...
Modelling of the Blood Plasma Species of Diagnostic Radiopharmaceuticals
... that biguanide is derived from the substitution of both oxygen atoms of biuret by imino (=NH) groups.7 ITB is similar to biguanide but one amidine group is replaced with a sulphur atom. These compounds are strong σ- and π-donating ligands that form stable complexes with transition metal ions in high ...
... that biguanide is derived from the substitution of both oxygen atoms of biuret by imino (=NH) groups.7 ITB is similar to biguanide but one amidine group is replaced with a sulphur atom. These compounds are strong σ- and π-donating ligands that form stable complexes with transition metal ions in high ...
Oscillatory concentration pulses of some divalent metal ions induced
... the reaction with solid NaHCO3) reaches a maximum concentration of 0.04 M. From these experiments we can conclude that in the BrO3 –SO32 oscillator, using the ‘‘optimal composition’’, in parallel with the changes in pH, the [SO32 ] also oscillates between 0 and 0.04 M. From our measurements of the [ ...
... the reaction with solid NaHCO3) reaches a maximum concentration of 0.04 M. From these experiments we can conclude that in the BrO3 –SO32 oscillator, using the ‘‘optimal composition’’, in parallel with the changes in pH, the [SO32 ] also oscillates between 0 and 0.04 M. From our measurements of the [ ...
Co-ordination engineering: when can one speak of an
... Then one derives the structure of 9, ∞2[Ag(µ-NO3)(µ-L)], with solely bridging co-ordination. Otherwise, if an excess of silver was used in the case of the NO3⫺ anion, tetradentate coordination was achieved. The structure of 10, ∞3[Ag3(µ3-NO3)3(µ3-L)2], is the example. An obvious variable in the silv ...
... Then one derives the structure of 9, ∞2[Ag(µ-NO3)(µ-L)], with solely bridging co-ordination. Otherwise, if an excess of silver was used in the case of the NO3⫺ anion, tetradentate coordination was achieved. The structure of 10, ∞3[Ag3(µ3-NO3)3(µ3-L)2], is the example. An obvious variable in the silv ...
Paramagnetic Metal Complexes as Water Proton
... The dependence of IH NMR image intensity on tisI I. Hlstorlcd Background sue relaxation times (which is the basis of image enFundamental investigations leading to the new area hancement using paramagnetic agents) is inherent in of NMR contrast agents are briefly discussed here. the basic principles ...
... The dependence of IH NMR image intensity on tisI I. Hlstorlcd Background sue relaxation times (which is the basis of image enFundamental investigations leading to the new area hancement using paramagnetic agents) is inherent in of NMR contrast agents are briefly discussed here. the basic principles ...
Electrochemical and X-ray studies of nickel(II)
... demands, N,N9-2-methylpropane-2,3-diyl-bis(salicylideneiminate)nickel(II) (1), N,N9-1,2-cyclohexyl-1,2-dyil-bis(salicylideneiminate)nickel(II) (2) and N,N9-2,3-dimethylbutane-2,3-diyl-bis(salicylideneiminate)nickel(II) (3), was studied by cyclic voltammetry and chronoamperometry in N,N9-dimethylform ...
... demands, N,N9-2-methylpropane-2,3-diyl-bis(salicylideneiminate)nickel(II) (1), N,N9-1,2-cyclohexyl-1,2-dyil-bis(salicylideneiminate)nickel(II) (2) and N,N9-2,3-dimethylbutane-2,3-diyl-bis(salicylideneiminate)nickel(II) (3), was studied by cyclic voltammetry and chronoamperometry in N,N9-dimethylform ...
High-spin Cyclopentadienyl Complexes, Part 6. σ/π
... Dimeric tri(tert-butyl)cyclopentadienyliron(II) bromide [Cp Fe(µ -Br)]2 (1) reacts with phenylmagnesium bromide to give the dinuclear di(cyclohexadienylidene) complex [(Cp Fe)2 (µ ,η 5 :η 5 H5 C6 =C6 H5 )] (2), and with mesitylmagnesium bromide either to the dinuclear complex [Cp Fe(µ ,η 5 ...
... Dimeric tri(tert-butyl)cyclopentadienyliron(II) bromide [Cp Fe(µ -Br)]2 (1) reacts with phenylmagnesium bromide to give the dinuclear di(cyclohexadienylidene) complex [(Cp Fe)2 (µ ,η 5 :η 5 H5 C6 =C6 H5 )] (2), and with mesitylmagnesium bromide either to the dinuclear complex [Cp Fe(µ ,η 5 ...
Complexes of Ethylenediaminetetracarboxylate Ligands
... To help make sense of these experimental observations, we turn to theoretical calculations, which can provide further insight into the structural and electronic properties of metal complexes. The relative energies of the various structural forms of M-edta-type complexes would be of use to experiment ...
... To help make sense of these experimental observations, we turn to theoretical calculations, which can provide further insight into the structural and electronic properties of metal complexes. The relative energies of the various structural forms of M-edta-type complexes would be of use to experiment ...
Angewandte Chemie : International Edition Highly
... The importance of industrial catalysis by platinum and palladium has motivated extensive studies of their gas phase chemistry.[1] Each metal atom is known to initiate cleavage of the C−H and C=C bonds of hydrocarbon precursors. The present study is believed to provide the first pure rotational spect ...
... The importance of industrial catalysis by platinum and palladium has motivated extensive studies of their gas phase chemistry.[1] Each metal atom is known to initiate cleavage of the C−H and C=C bonds of hydrocarbon precursors. The present study is believed to provide the first pure rotational spect ...
Introductory Guide to Organonickel Chemistry - Wiley-VCH
... In addition to the s-bonding, there operates another bonding mechanism, socalled ‘‘back bonding’’ or ‘‘back donation’’. As is illustrated in Figure 1.2(c), the p orbital of the CO has a proper symmetry with the dp atomic orbital of the Ni, and these two interact to each other to make up a new p-bo ...
... In addition to the s-bonding, there operates another bonding mechanism, socalled ‘‘back bonding’’ or ‘‘back donation’’. As is illustrated in Figure 1.2(c), the p orbital of the CO has a proper symmetry with the dp atomic orbital of the Ni, and these two interact to each other to make up a new p-bo ...
09_chapter 4
... evident from the work presented in the preceding chapter. Catalysts with oxy anion of iron, crystallized into different crystal structure like spinels viz; AFe2O4 (A= Cu2+, Co3+ and Ni2+) were investigated to explore their suitability under harsh reaction conditions. Fe-based spinel oxides offer goo ...
... evident from the work presented in the preceding chapter. Catalysts with oxy anion of iron, crystallized into different crystal structure like spinels viz; AFe2O4 (A= Cu2+, Co3+ and Ni2+) were investigated to explore their suitability under harsh reaction conditions. Fe-based spinel oxides offer goo ...
summary spectral and magnetic investigations of
... with reference to main group elements and probably also with early transition metals us due to the potential bond formation with soft or hard donor resulting into what is now known as anisobidentate character of the ligands. There has been little systematic research on have the stereo chemistry and ...
... with reference to main group elements and probably also with early transition metals us due to the potential bond formation with soft or hard donor resulting into what is now known as anisobidentate character of the ligands. There has been little systematic research on have the stereo chemistry and ...
... All the compounds and solvents used were purchased from Aldrich and Sigma and used as received without further purification. Elemental microanalyses of the separated ligands for C, H, and N were determined on Automatic Analyzer CHNS Vario ELIII, Germany. The 1H-NMR spectrum was obtained with a JEOL ...
Comparison for Bonding Situation between Tetrylone and Tetrylene
... carbene ligands [22-28] and heavier homologues where E = Si to Pb have been studied extensively in recent past [29-34] since carbene ligands were found to be excellent catalysts in various chemical reactions [35-41]. It has been proposed that carbodiphosphoranes may even be better ligand than carben ...
... carbene ligands [22-28] and heavier homologues where E = Si to Pb have been studied extensively in recent past [29-34] since carbene ligands were found to be excellent catalysts in various chemical reactions [35-41]. It has been proposed that carbodiphosphoranes may even be better ligand than carben ...
A Stable Five-Coordinate Platinum(IV) Alkyl
... Transformation of 1 into 2 was not observed by thermal activation. Instead, heating a solution of 1 in cyclohexane at 90 °C in the dark led to decomposition to a variety of products, including platinum black, over the course of half a day. The expected product of C-C reductive elimination from 1, et ...
... Transformation of 1 into 2 was not observed by thermal activation. Instead, heating a solution of 1 in cyclohexane at 90 °C in the dark led to decomposition to a variety of products, including platinum black, over the course of half a day. The expected product of C-C reductive elimination from 1, et ...
Title Regioselective Electrophilic C
... ligands for transition metals.5 For example, Arduengo-type carbenes that contain an aryl wingtip group as N-substituent form metallacycles through C–H bond activation when bound to a late transition metal such as ruthenium, palladium or platinum,6 and this process has also been accounted for the dea ...
... ligands for transition metals.5 For example, Arduengo-type carbenes that contain an aryl wingtip group as N-substituent form metallacycles through C–H bond activation when bound to a late transition metal such as ruthenium, palladium or platinum,6 and this process has also been accounted for the dea ...
Pincer Complexes. Applications in Catalysis
... of these complexes have shown activity in the dehydrogenation of alkanes to alkenes. However, the extremely low reaction rates and the low turnover numbers or the instability of the employed catalysts under the reaction conditions16 has limited the use of these species. In 1976 Moulton and Shaw repo ...
... of these complexes have shown activity in the dehydrogenation of alkanes to alkenes. However, the extremely low reaction rates and the low turnover numbers or the instability of the employed catalysts under the reaction conditions16 has limited the use of these species. In 1976 Moulton and Shaw repo ...
How High the Spin? Allowed and Forbidden Spin States in
... interaction between the metal center and the donor atoms, and is controlled by the overlap and difference in electronegativity of both s- and p-type metal– ligand interactions. Its magnitude obtained from visible spectra, for example, is empirically expressed through the spectrochemical series of th ...
... interaction between the metal center and the donor atoms, and is controlled by the overlap and difference in electronegativity of both s- and p-type metal– ligand interactions. Its magnitude obtained from visible spectra, for example, is empirically expressed through the spectrochemical series of th ...
Metal carbonyl
Metal carbonyls are coordination complexes of transition metals with carbon monoxide ligands. Metal carbonyls are useful in organic synthesis and as catalysts or catalyst precursors in homogeneous catalysis, such as hydroformylation and Reppe chemistry. In the Mond process, nickel carbonyl is used to produce pure nickel. In organometallic chemistry, metal carbonyls serve as precursors for the preparation of other organometalic complexes.Metal carbonyls are toxic by skin contact, inhalation or ingestion, in part because of their ability to carbonylate hemoglobin to give carboxyhemoglobin, which prevents the binding of O2.