The role of lithium tetrahydroaluminate in the formation of nanodimensional nickel hydrogenation catalysts

Belykh, L. B.; Titova, Yu. Yu.; Umanets, V. A.; Рохин, А. В.; Schmidt, Friedrich

doi:10.1016/j.apcata.2011.04.047

Cited by 14 publications

(3 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This result may be explained by bonding of DAD(-CH 3 ) with AlEt 3 and higher coordination desaturation of the nickel complexes that are active in catalysis, which are most likely to be cluster compounds of nickel. 2,14 Systems based on complexes of Ni[DAD(-CH 3 )] 2 and aluminum and boron containing co-catalysts (AlEt 3 , AlEt 2 Cl, AlEtCl 2 , B(C 6 F 5 ) 3 , BF 3 ÁOEt 2 ) are active in polymerization of the lowest a-olefins. Table I complexes observed in the spectra can vary.…”

Section: Resultsmentioning

confidence: 99%

EPR Spectroscopy of catalytic systems based on nickel complexes of 1,4-diaza-1,3-butadiene (α-diimine) ligands in hydrogenation and polymerization reactions

Titova

Belykh

Schmidt

2015

Low Temperature Physics

View full text Add to dashboard Cite

Articles you may be interested inAdsorption and ring-opening of lactide on the chiral metal surface Pt(321) S studied by density functional theory J. Chem. Phys. 142, 044703 (2015); 10.1063/1.4906151Role of the reaction intermediates in determining PHIP (parahydrogen induced polarization) effect in the hydrogenation of acetylene dicarboxylic acid with the complex [Rh (dppb)]+ (dppb: 1,4bis(diphenylphosphino)butane)EPR spectroscopy is used to study catalytic hydration and polymerization reaction systems based on a-diimine complexes of Ni(0) and Ni(II) with the general formula NiBr 2 (DAD-R) (R ¼ -C 3 H 7 or -CH 3 ) or Ni(DAD-CH 3 ) 2 (DAD(-C 3 H 7 ) ¼ 1,4-bis(2,6-diiso-propylphenyl)-2,3-(dimethyl-1,4diazabuta-1,3-diene, DAD(-CH 3 ) ¼ 1,4-bis(2,6-dimethylphenyl)-2,3-dimethyl-1,4-diazabuta-1,3diene)), in combination with Lewis acids (AlEt 3 , AlEt 2 Cl, AlEtCl 2 , B(F 5 C 6 ) 3 , BF 3 ÁOEt 2 ). Ni(I) complexes of the form (DAD-R)NiX 2 AlX 0 y (C 2 H 5 ) 3-y composition (an aluminum atom can be replaced by a boron atom) were identified, where R ¼ -CH 3 or -C 3 H 7 , X ¼ Br, and X 0 ¼ Cl or -C 2 H 5 and a-diimine anion radicals are included in derivatives of aluminum or boron. Oxidation reactions of the Ni(DAD-CH 3 ) 2 complex with aluminum alkyl halides and boron derivatives with formation of paramagnetic nickel complexes are observed. It is found that there is no direct relationship between the polymerization activity of ethylene or hydration of the alkenes and the concentration of paramagnetic particles. V C 2015 AIP Publishing LLC.

show abstract

Section: Resultsmentioning

confidence: 99%

EPR Spectroscopy of catalytic systems based on nickel complexes of 1,4-diaza-1,3-butadiene (α-diimine) ligands in hydrogenation and polymerization reactions

Titova

Belykh

Schmidt

2015

Low Temperature Physics

View full text Add to dashboard Cite

show abstract

“…However, its use as a routine option has not been extended due to the lack of mild and environmentally friendly synthetic methods. Low-valent nickel complexes are commonly synthesized under an inert atmosphere by reaction with strong reducing agents, including the powerful hydride donors LiHBEt 3 , LiAlH 4 , and [( i Bu) 2 Al(μ-H)] 2 . These reaction conditions are some of the limitations faced by new green methodologies.…”

Section: Introductionmentioning

confidence: 99%

Synthesis of Low-Valent Nickel Complexes in Aqueous Media, Mechanistic Insights, and Selected Applications

et al. 2014

View full text Add to dashboard Cite

The synthesis of nickel(0) complexes usually requires the employment of strong reducing agents, including powerful hydride donors such as LiHBEt3, LiAlH4, and DIBAL-H. Herein, we have reduced the Ni(II) complex [(dippe)NiCl2] (1a) at room temperature by using KOH in aqueous media to yield the low-valent complex [Ni(dippe)2] (4a) as the main product, along with the formation of dippeO2. In order to gain some insight into the reaction mechanism, a series of intermediates were isolated and characterized at different reaction stages. As a result, both Ni(II) hydroxo-bridge (2b) and hydride (3b) complexes were identified as key intermediates. Additionally, the use of water as a hydrogen source in nickel-mediated processes was also investigated and successfully applied to the hydrodefluorination, hydrodesulfurization, and hydrogenation of selected organic substrates.

show abstract

“…Since 2004 we have been engaged in detailed investigations of the processes occurring during the formation and functioning of Ziegler hydrogenation catalytic systems [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15]. Using M(acac) 2 -Red (where M = Co, Ni; Red = AlEt 3 , LiAlH 4 , AlEt 2 (OEt), LiAlH(tert-BuO) 3 ) it was shown that the interaction of acetylacetonate complexes of cobalt, nickel, or palladium with AlEt 3 or LiAlH 4 produced nanoparticles consisting of a metal core (0.7-5 nm) stabilized by a ligand shell.…”

Section: Introductionmentioning

confidence: 99%

Formation and Functioning of Nickel Bis-(acetylacetonate)-Based Multicomponent Catalytic Systems for Di- and Oligomerization of Ethylene: New Mechanistic Aspects

Titova

Schmidt

2021

Catalysts

View full text Add to dashboard Cite

The paper summarizes new information on the formation and functioning of Ni(acac)2-based multicomponent (Ziegler) systems for oligo- and polymerization of ethylene. It turns out that catalytically active sites formed in these systems are deposited on nickel-containing nanoparticles generated via the interaction of the starting components directly in the reaction system. It is shown that the activity, productivity, and composition of the target products depend on the water content in the initial solvent, all other things being equal. A model of nanosized nickel-containing particles formed during the interaction of Ni(acac)2 and diethylaluminum chloride or ethylaluminum sesquichloride is presented.

show abstract

The role of lithium tetrahydroaluminate in the formation of nanodimensional nickel hydrogenation catalysts

Cited by 14 publications

References 31 publications

EPR Spectroscopy of catalytic systems based on nickel complexes of 1,4-diaza-1,3-butadiene (α-diimine) ligands in hydrogenation and polymerization reactions

EPR Spectroscopy of catalytic systems based on nickel complexes of 1,4-diaza-1,3-butadiene (α-diimine) ligands in hydrogenation and polymerization reactions

Synthesis of Low-Valent Nickel Complexes in Aqueous Media, Mechanistic Insights, and Selected Applications

Formation and Functioning of Nickel Bis-(acetylacetonate)-Based Multicomponent Catalytic Systems for Di- and Oligomerization of Ethylene: New Mechanistic Aspects

Contact Info

Product

Resources

About