Collect. Czech. Chem. Commun. 1981, 46, 1600-1606
https://doi.org/10.1135/cccc19811600

Mechanism of anionic coordination dimerization of isoprene

Jan Bartoňa, Karel Volkab, Miroslav Kašparc and Vlastimil Růžičkaa

a Department of Organic Technology, Prague Institute of Chemical Technology, 166 28 Prague 6
b Department of Analytical Chemistry, Prague Institute of Chemical Technology, 166 28 Prague 6
c Institute of Macromolecular Chemistry, Czechoslovak Academy of Sciences, 162 06 Prague 6

Abstract

The mechanism of controlled anionic coordination dimerization of isoprene (i.e. 2-methyl-1,3-butadiene) in the system tetrahydrofuran-isoprene-alkali metal-dialkylamine was investigated by using absorption spectrophotometry in the range of visible radiation and gas chromatography. The effect of the alkali metal (Li, Na, K) and dialkylamine (dicyclohexylamine, N-isopropylcyclohexylamine, N-methylisopropylamine) on the absorption spectra was tested. By comparing chromatographic and spectrophotometric data, the absorption bands in the range of visible radiation were identified with the existence of π-complexes between oligomeric forms of isoprene and alkali metal dialkylamide.