Evidence of coordinative chain transfer polymerization of isoprene using iron iminopyridine/ZnEt2 catalytic systems†
Abstract
Isoprene polymerization using iminopyridine-supported iron complexes combined with AliBu3/[B(C6F5)4][CPh3] was carried out in the presence of ZnEt2 as the chain transfer agent (CTA). Detailed studies revealed that the Mn of the resulting polyisoprenes and the rate of polymerization decrease steadily as the amount of CTA increases while preserving the catalyst selectivity. These results highlight the first example of a reversible iron-mediated chain transfer polymerization of isoprene.