The Oligomerization of Butadiene with an Iron Complex Catalyst

Abstract

Abstract The oligomerization of butadiene with the catalyst system of iron(III) acetylacetonate and triethylaluminum has been studied. The products obtained by the use of this catalyst consist of two types, one of which is dimers and trimers, and the other is polybutadiene, with an average polymerization degree of seven. The dimers are 3-methylhepta-1, 4, 6-triene and cycloocta-1, 5-diene. The trimers have been confirmed to be n-dodeca-1, 3, 6, 10-tetraene and a branched isomer. The effects of the ratio of the catalyst components to the concentration of the catalyst have been also studied. From these results, it has been concluded that oligomerization proceeds by a mechanism different from that of polymerization. To elucidate a transition state for oligomerization, the visible light spectra and the magnetic susceptibility of the reaction solution have been measured and a complex in which butadiene coordinates to reduced iron atom has been assumed as the transition state.