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Nickel-catalyzed cyclodimerization butadiene

As illustrated in the early achievements from Reppe on the cyclotetramerization of acetylene and from Wilke on the cyclodimerization and cyclotrimerization of butadienes, nickel-catalyzed cycloadditions possess considerable potential in the construction of medium ring systems. Pioneering studies by Wender have demonstrated many practical implications that have advanced the... [Pg.363]

Homogeneous nickel complexes proved to be versatile catalysts in dimerization and trimerization of dienes to yield different oligomeric products.46-55 Depending on the actual catalyst structure, nickel catalyzes the dimerization of 1,3-butadiene to yield isomeric octatrienes, and the cyclodimerization and cyclotrimerization to give 1,5-cyclooctadiene and all-trans-l,5,9-cyclododecatriene, respectively46 56 [Eq. (13.13)]. Ziegler-type complexes may be used to form cis,trans,trans-1,5,9-cyclododecatriene37,57 58 [Eq. (13.14)], which is an industrial intermediate ... [Pg.730]

The first catalytic cyclodimerization of 1,3-butadiene (BD) to 1,5-cycloocta-diene using modified Reppe catalysts was reported by Reed in 1954 [4], and only two years later Wilke reported on the titanium-catalyzed synthesis of cyclo-dodecatrienes from BD [5]. It remained for Wilke and his co-workers to show the tremendous versatility and scope of the nickel-catalyzed cyclooligomerizations of... [Pg.368]

We have previously used this method to establish allyl isomerization events in nickel catalyzed cyclodimerization of butadiene, and describe here our application to the polymerization mechanism. [Pg.310]

Both bis(l,5-cyclooctadiene)nickel(0) and bis(acrylonitrile)nickel(0) catalyze the polymerization of allene to highly crystalline linear polymers (451). With compounds such as tri-o-tolyl phosphite, bis(acrylo-nitrile)nickel in hydrocarbon catalyzes the cyclodimerization of butadiene to 1,5-cyclooctadiene, whereas in alcohols it catalyzes the... [Pg.310]

Chiral aminophosphane-phosphinites (AMPP), prepared by the reaction of chloro(diphenyl)-phosphane with optically active amino alcohols, such as ephedrines, prolinol and A -methyl-phenylglycinol, are used as ligands in transition metal catalyzed cyclodimerization of butadiene to 4-vinylcyclohexene62,10 . With a nickel(0)LJ catalyst (L = Proliphos), (—)-4-vinylcyclo-hexene with 15% ee was obtained in 50% yield6. ... [Pg.473]

A recently reported cyclodimerization reaction of butadiene is the formation of 2-methylenevinylcyclopentane 170 171>. The reaction is catalyzed most effectively by rra/jj-bis (triethylphosphine)chloro-(o-tolyl)nickel in the presence of alcohol. It is interesting that negligible amounts of cyclooctadiene and cyclo-dodecatriene are formed with this catalyst. [Pg.75]

The nickel(O) complex Ni4(CNBu07 catalyzes reduction of acetylenes to olefins, isocyanides and cyanides to amines, as well as cyclotrimerization of acetylene and cyclodimerization of butadiene. Reduction of isocyanides is also catalyzed by other clusters (Chapter 13). Isocyanide copper compounds catalyze addition of CH2CIY (Y = COOR, COR, CN) to olefins leading to the formation of cyclopropane derivatives... [Pg.641]

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-... [Pg.38]


See other pages where Nickel-catalyzed cyclodimerization butadiene is mentioned: [Pg.641]    [Pg.143]    [Pg.168]    [Pg.17]    [Pg.374]   
See also in sourсe #XX -- [ Pg.310 ]




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1,3-Butadiene cyclodimerization

Cyclodimerization

Cyclodimerizations

Nickel-catalyzed

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