Nickel acetylacetonate, catalyst

The anionic nickel acetylacetonate catalyst gives only the cis, cis, trans product. Intermediate catalysts have already been seen to give cis, cis, cis structures which do not terminate but produce cis polybutadiene. This will also be seen later with cobalt iodide. At high temperatures or with strongly cationic systems the cyclic dodecatrienes are isomerized to the most stable trans, trans, trans structure. 

The first attempts to synthesis asymmetric polyisocyanides are recent ones [30]. Asymmetric polymerization of racemic isocyanide (Xllla) with nickel chloride or nickel acetylacetonate catalyst was attempted in the presence of chiral solvents, (-)-borneol or (+)-sec-butyl-alcohol, or in the presence of (+)-nickel alaninate with the racemic a-phenyl-ethylisocyanide (Xlllb), but the polymers did not show any activity. 

Combination of nickel bromide (or nickel acetylacetonate) and A. A -dibutylnorephcdrinc catalyzed the enantioselective conjugate addition of dialkylzincs to a./Tunsaturated ketones to afford optically active //-substituted ketones in up to ca. 50% ee53. Use of the nickel(II) bipyridyl-chiral ligand complex in acetonitrile/toluenc as an in situ prepared catalyst system afforded the //-substituted ketones 2, from aryl-substituted enones 1, in up to 90% ee54. 

The liquid-phase reduction method was applied to the preparation of the supported catalyst [27]. Virtually, Muramatsu et al. reported the controlled formation of ultrafine Ni particles on hematite particles with different shapes. The Ni particles were selectively deposited on these hematite particles by the liquid-phase reduction with NaBFl4. For the concrete manner, see the following process. Nickel acetylacetonate (Ni(AA)2) and zinc acetylacetonate (Zn(AA)2) were codissolved in 40 ml of 2-propanol with a Zn/Ni ratio of 0-1.0, where the concentration of Ni was 5.0 X lO mol/dm. 0.125 g of Ti02... 

Ligand-free catalysts have been prepared from the following types of nickel(II) compounds nickel salts of long-chain aliphatic or aromatic carboxylic acids (10, 11) or of sulfonic acids (11), nickel enolates of /3-diketones (11) [e.g., nickel acetylacetonate (4, 12)] or their imino derivatives (11, 13), nickel phenolates (11), dithiocarbamates (14), and mer-captides (15). 

Nickel-based Ziegler catalysts can be prepared using halogen-free or-ganoaluminum compounds of low Lewis acidity, e.g., dialkylaluminum alkoxides. However, the catalytic properties of these systems differ remarkably from those described above. The nickel components in such a case may be nickel acetylacetonate, or the nickel enolates of various other /3-dicarbonyl compounds (44, 45), in particular such halogenated /3-dicarbonyl compounds as hexafluoroacetylacetone (44, 46). 

Examples of w-allylnickel-X compounds (X = anionic ligand) other than 77-allylnickel halides which have been used in combination with (alkyl)aluminum halides as olefin oligomerization catalysts are 7r-allyl-nickel acetylacetonate (11) (Section III), 7r-allylnickel aziridide (4, 56), and bis(7r-allyl)nickel (6) (59). In addition to ir-allylnickel halides, organo-nickel halides such as tritylnickel chloride (60, 61) and pentafluoro-phenylbis(triphenylphosphine)nickel bromide (62), or hydridonickel halides, e.g., trans-hydridobis(triisopropylphosphine)nickel chloride (12) (Section III), give active catalysts after activation with aluminum halides... 

Oxidative addition of the silyl species to nickel is followed by insertion of unsaturated substrates. Zero-valent nickel complexes, and complexes prepared by reducing nickel acetylacetonate with aluminum trialkyls or ethoxydialkyls, and in general Ziegler-Natta-type systems, are effective as catalysts (244, 260-262). Ni(CO)4 is specific for terminal attack of SiHCl3 on styrene (261). 

Nickel acetylacetonate is used as a catalyst in hydrogenation and other organic reactions. 

We have tested successfully a variant of this Mukaiyama procedure, that has been described in more detail subsequently (45-46). Our prior experience with nickel(II) catalysts impregnated on clays and nicknamed (47) "claynick" (48) and the convenience of a supported catalyst (49-50) made us opt for clay-impregnated nickel acetylacetonate as the catalyst. 

Nickel catalysts are also efficient in promoting the coupling of halopyridines and amines. In the presence of nickel acetylacetonate and Arduengo type carbene precursors chloropyridines were coupled with a series of amines to give the aminopyridines in high yield. 3-Chloropyridine, for example, reacted with A -mcthylanilinc to yield the anilinopyridine in 93% (7.75.), Of the carbene precursors tested l,3-bis(2 ,6 -... 

The monomers dealt with can be polymerized by various mechanisms, not only by ROMP. For example, a rapid polymerization of norbornadiene occurs using a homogeneous catalytic system consisting of nickel acetylacetonate or a nickel-phosphine complex, such as nickel bis-(tri-n-butylphosphine) dichloride (NiCl2(TBP)2) or nickel bis-(tricyclohexylphosphine) dichloride (NiCl2(TBP)2). Nickel acetylacetonate as catalyst is known to initiate rather a classical vinyl polymerization (7). The classical vinyl polymerization... 

Table X, however, shows clearly that, in contrast to the butadiene-ethylene system, triphenylphosphine is the most successful ligand. We will return to this point later. The preparation of DMCDeT on a laboratory scale can be conveniently carried out by dissolving the nickel-ligand catalyst [which may be prepared by reduction of nickel acetylacetonate or directly from bis(cyclooctadiene)nickel and triphenylphosphine] in a solution of butadiene in toluene. Butyne is then added to give a butadiene-to-butyne ratio of 5-10 1. The reaction is conducted at 20° C and the contraction in volume is observed. The reaction is terminated at the break in the contraction curve (Fig. 3).

Optically active P-hydroxy /V-methyl sulfoximines have been used as catalysts for the enantioselective transfer of an ethyl group from diethylzinc to aldehydes to give secondary alcohols in enantiomeric excesses of 61-88%.127,135 Related chiral ligands have been used with nickel acetylacetone to promote the enantioselective Michael addition of diethylzinc to chalcones.136... 

Molina, R., M. A. Centeno, and G. Poncelet, a-Alumina-Supported Nickel Catalysts Prepared with Nickel Acetylacetonate. 1. Adsorption in the Liquid Phase , J. Phys. Chem. B. 1999,103, 6036-46. 

Two isomeric 1,5,9-cyclododecatrienes, namely, trans,trans,cis-CijH 18 (XLVI) and trans,trans,trans-CuHis (XLVII), are formed in good yield by the cyclic trimerization of butadiene using certain Ziegler-type catalysts 247, 250, 251, 252). The formation of these 12-membered ring hydrocarbons probably proceeds via metal 7r-complexed intermediates. When the cyclic triene (XLVII) is treated with nickel acetylacetonate and... 

What compounds are the active catalysts in this process By this method of catalyst preparation we do not obtain a mixture of indefinite composition, but TT-complexes which can be isolated and are mostly crystalline. If, for instance, nickel acetylacetonate is reduced in the presence of P(CeH5)3 we obtain a new compound, Ni-(0)-[P(CeH5)3]4. This compound is itself an active catalyst for the cyclo-oligomerization of butadiene, producing about 65 to 70% cyclo-octadiene, 20% vinylcyclohexene, and 10% cyclododecatriene. Instead of P(CeH5)3 we can introduce As(CeH5)3 and isolate Ni-(0)-[As(CeH5)3]4 as an active cata-... 

Nickel acetylacetonate monohydrate is a better basic catalyst than triethylamine for the condensation of Meldrum s acid and the lactim ether. The yields are higher and the product is easier to purify. 

Osawa, T., Mita, S., Iwai, A., Takayasu, O., Hashiba, H., Hashimoto, S., Harada, T., and Matsuura, I. (2000) Enantio-differentiating hydrogenation of methyl acetoacetate over tartaric acid-NaBr-modfied supported nickel catalyst prepared Irom nickel acetylacetonate, J. Mol. Catal. A Chem. 157, 207-216. 

Tetrasodium EDTA Trisodium EDTA catalyst, sealants Triethylene diamine catalyst, shoe soles Diazabicycloundecene catalyst, SHOP process Nickel chloride hexahydrate catalyst, silicone elastomers Dibutyltin dilaurate catalyst, silicone rubber curing Bis (2,4-dichlorobenzoyl) peroxide catalyst, silicone rubber 2-component Chloroplatinic acid catalyst, slabstock N,N,N -Trimethyl-N -hydroxyethylbisaminoethylether catalyst, SO2 oxidation Cesium sulfate catalyst, solder fluxes Isooctyl acid phosphate catalyst, soldering fluxes Ethyl acid phosphate 2-Ethylhexyl phosphate Stearyl acid phosphate catalyst, solid fuels Ferric acetylacetonate catalyst, solid rocket fuels Copper nitrate (ic) catalyst, solvent extractants Ethyl acid phosphate 2-Ethylhexyl phosphate Stearyl acid phosphate catalyst, solvent hydrogenation beer-making hops... 

In 2010 [95], Ozaki and collaborators mixed a furan resin with iron, cobalt, or nickel acetylacetonates and carbonized the mixture in N2 at 600 to 1,000 °C. The resulting material was ball milled and then acid washed to remove excess metal. The best catalyst was obtained with the Co complex carbonized at 800 °C. Its Fonset in 0.5 M H2SO4 was 0.62 V vs. RHE. The catalyst had a specific surface area of 211 m /g and its N/C ratio was 0.035. Its ORR activity was explained by the formation of carbon nanoshells, but also by N doping of the catalyst carbonaceous material. 

The thermal polymerization of butadiene yields, according to Ziegler et al., a mixture of vinylcyclohexene with at most 15% of cyclooctadiene (95, 96). In 1954 Reed (97) discovered the catalytic cyclodimerization of butadiene to cycloocta-1,5-diene with Reppe catalysts, with a 30-40% conversion at 120-130° C. Wilke et al. recently synthesized a very efficient class of catalyst. If nickel-acetylacetonate is treated with metal alkyls (especially aluminum alkyls) in the presence of electron-donating compounds (mainly cycloolefins), new tt complexes of nickel are obtained which catalyze the cyclo-oligomerization of butadiene (98, 99). Using cycloocta-1,5-diene as the olefinic component, the well-crystallized, faintly yellow bis(cycloocta-... 

Compound (LXVI) is particularly interesting as it undergoes a 1,7 addition with tetracyanoethylene. This transannular addition is possible since the opposite pairs of double bonds in (LXVI) parallel each other at a distance of only about 2.7 A, which must lead to appreciable ir-orbital interaction 105). In the presence of acetylene, with Ni(CO)2 2P(OC6H5)3 as the catalyst, a co-cyclopolymerization of allene to 3,5- and 3,6-dimethylene-cyclohexene (LXVII) and (LXVIII), respectively, is possible (106). With nickel acetylacetonate as catalyst, (LXVII) and 3,5,7-trimethylenecyclo-octene (LXVIII) are produced in 45% and 5% yield respectively. 106). This reaction makes exo-methylene cyclic compounds which are unsaturated easily accessible. The chemistry of (LXVII) has been studied in some detail 107). 

The cleavage of (212 R = COMe or COPh) by lithium dialkylcuprates has been developed into a preparative route for the synthesis of y6-unsaturated ketones in yields of 60— 98 %. The cleavage of cyclopropyl ketones by lithium dialkylcuprates can also be effected by aluminium trialkyls, with nickel acetylacetonate as catalyst. ... 

Treatment of buca-l,3-diene with titaniumfiv) chloride and diethylaluminium chloride gave a mixture of cis,rrans,rran cyclododeca-l,5,9-triene and all-trons-cyclohexadeca-l,5,9,13-tetraene. The co-dimerization of buta-1,3-diene and iso-prene or trons-1-piperylene by nickel acetylacetonate in the presence of triphenyl-phosphite and perhydro-9b-alumophenalene to give 1- or 3-methylcyclo-octa-1,5-diene, has been studied. Buta-1,3-diene has been cyclo-oligomerized in the presence of a nickel catalyst to give a mixture all-rrans-cyclododeca-l,5,9-triene, all trans-cyclohexadeca-1,5,9,13-tetraene and 11-vinyl-all-trans-cyclotetradeca-1,4,8-triene, in the ratio of 80 15 5, respectively, in 90% combined yield. The catalytic... 

Dienones (12) are converted into 2,4-dienones (13) in good yield and with high selectivity in the presence of 1% nickel acetylacetonate. The reaction is carried out at 165 °C in N-methyl-2-pyrrolidone, and at the end of the reaction the catalyst is readily recovered and can be recycled. 

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