Metal complexes in catalytic conversions of olefins. 4. Heterogenization of nickel complexes on chemically modified silochrome surface; activity and selectivity in ethylene dimerization

1990 ◽  
Vol 39 (3) ◽  
pp. 448-451 ◽  
Author(s):  
D. B. Furman ◽  
A. O. Ivanov ◽  
A. Yu. Olenin ◽  
A. Yu. Vasil'kov ◽  
M. K. Munshieva ◽  
...  
Keyword(s):  
Metal Complexes ◽  
Surface Activity ◽  
Nickel Complexes ◽  
Ethylene Dimerization ◽  
Chemically Modified

Übergangsmetallkomplexe mit Schwefelliganden, LXXVI Redox- und Additionsreaktionen von Nickelkomplexen mehrzähniger Thioether-Thiolat-Liganden. Röntgenstrukturanalysen von (NMe4)2[Ni(′S2′)2] und [Ni(′S4 – C3′)(PMe3)] / Transition Metal Complexes with Sulfur Ligands, LXXVI Redox and Addition Reactions of Nickel Complexes with Multidentate Thioether-Thiolato Ligands. X-Ray Structure Determinations of (NMe4)2[Ni(′S2′)2] and [Ni(′S4–C3′)(PMe3)]

1991 ◽  
Vol 46 (12) ◽  
pp. 1601-1608 ◽  
Author(s):  
Dieter Sellmann ◽  
Stefan Fünfgelder ◽  
Falk Knoch ◽  
Matthias Moll
Keyword(s):  
Transition Metal ◽  
Metal Complexes ◽  
Structure Analysis ◽  
Transition Metal Complexes ◽  
Nickel Complexes ◽  
Addition Reactions ◽  
Coordination Geometry ◽  
X Ray ◽  
Square Planar ◽  
Structure Determinations

In order to elucidate specific properties of nickel sulfur complexes, redox and addition-elimination reactions of [Ni(′OS4')]2, [Ni(′NHS4')]2, [Ni(′S5')], [Ni('S4—C5')], and [Ni('S4—C3')] were investigated ('OS4′ 2' = 2,2'-bis(2-mercaptophenylthio)diethylether(2—), 'NHS4'2- = 2,2'-bis(2-mercaptophenylthio)diethylamine(2—), 'S5'2- = 2,2'-bis(2-mercaptophenylthio)diethylsulfide(2—), 'S4-C5'2- = 1,5-bis(2-mercaptophenylthio)pentane(2—), 'S4—C3'2- = 1,3-bis(2-mercaptophenylthio)propane(2—)).Cyclovoltammetry proves the complexes to be redox inactive between —1.4 and +0.8 V vs. NHE. Above +0.8 V the complexes are irreversibly oxidized, below —1,4 V desalkylation takes place and [Ni(′S,′)2]2- is formed. An X-ray structure analysis was carried out of (NMe4)2[Ni(′S2')2], which shows a planar anion with the Ni center in a nearly perfect square planar coordination. Distances and angles are practically identical to those in the [Ni(′S2')2-] monoanion.The complexes coordinate only phosphines as coligands, but thioether donors simultaneously decoordinate and, dependant of reaction temperature, mono- or trisphosphine complexes are formed. [Ni(′S4—C3')(PMe3)] was characterized by X-ray structure analysis and exhibits a square pyramidal coordination geometry.

Metal complexes as ligands. X. Investigation of valency and substituent effects in binuclear complexes derived from tetradentate salicylaldimines

1972 ◽  
Vol 25 (1) ◽  
pp. 45 ◽  
Author(s):  
S Kokot ◽  
CM Harris ◽  
E Sinn
Keyword(s):  
Metal Complexes ◽  
Substituent Effects ◽  
Nickel Complexes ◽  
Magnetic Interactions ◽  
Binuclear Complexes ◽  
Electronic Effects ◽  
Metal Chlorides ◽  
Limited Sampling ◽  
Phenyl Rings ◽  
The Difference

A series of binuclear complexes has been formed by using planar copper(11) complexes (CUTSB) of tetradentate Schiff bases (TSB) as ligands to coordinate with metal chlorides. The binuclear complexes, (CuTSB)MCln (M = Cu11, Fe111, Mn11; n. = 2, 3), all exhibit pairwise antiferromagnetic interactions. The nickel complexes (NitsB)Mcln (M = FeIII, MnII) can be formed similarly, but the nickel atoms are diamagnetic so that no significant magnetic interactions are expected. The effect of 5-Cl, 5-Br, and 5,6-benzo substituents in the phenyl rings of the TSB groups on the strength of the antiferromagnetic interactions was examined in the complexes (CUTSB)CuCl2. Although the presence of a substituent usually increases the strength of the interaction, this trend is not systematic and there is no reason to attribute it to electronic effects of ring substituents. In (CUTSB)MCln, the main difference between the complexes with M = Fe111 and M = Mn11 is the difference in the valencies of the two d5 metals. In our limited sampling (one complex of each type), the interaction is stronger between iron(111) and copper(11) than between the manganese(11) and copper(11). These complexes form as hydrates, and since iron(111) and manganese(11) prefer octahedral environments, it is probable that one and two molecules of water respectively are coordinated to these metals. In the case where M = FeIII, N�ssbauer measurements indicate that this is so.

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