Oligomerização e telemirização de butadieno na presença de catalizadores de niquel, ferro e paladio, ancorados em polimeros organicos

AUTOR(ES)
DATA DE PUBLICAÇÃO

1987

RESUMO

Nickel, iron and palladium were anchored to poly(vinylpyridines) and to poly(styrene/divinylbenzene) funcionalized with 2,2 -bipyridyl. The catalytic systems with nickel were highly active and selective for the cyclotrimerization of butadiene to 1,5,9-cyclododecatriene (CDT; 62,3 to 91,7%). The oligomerization reactions of butadiene in the presence of the heterogeneized iron catalysts were slow, similar to the corresponding homogeneous systems. The iron containing poly- (vinylpyridines) showed low selectivity for the oligomerization. However iron anchored to poly(styrene/divinylbenzene) funcionalized with 2,2 -bipyridyl formed only the cyclodimers 4-vinylcyclohexene (VCH, 41%) and cyclooctadiene-1,5 (COD, 37%). The telomerization of butadiene with methanol in the presence of palladium(II) containing polymers was only possible with the addition of triphenylphosphine and furnished ratios of the products which were different from the homogeneous catalysis reaction. In alI cases a certain quantity of the metal was leached from the polymers during the reactions and, with the exception of the poly-(4-vinylpyridine) nickel, recycling of the catalyst was not possible. The possible mechanisms of the catalysis are discussed by comparing the results of the global molar conversions and selectivities with those described for the corresponding homogeneous systems.

ASSUNTO(S)

butadieno catalisadores polimeros

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