Acyclic diene metathesis (ADMET) polymerization using aryloxy tungsten-based classical catalytic systems

摘要

The range of ADMET polymerization active catalysts has been expanded to include classical catalytic systems. The acyclic diene metathesis (ADMET) polymerization of hydrocarbon dienes has been performed using the aryloxy-tungsten complexes WCl4(O-2,6-C6H3Ph2)(2) (4), W(O)Cl-2(O-2,6-C6H3Br2)(2) (5) and WCl4(O-2,6-C6H3Br2)(2) (6) as the precatalytic species in combination with tetrabutyltin, tetramethyltin and tri-n-butyltin hydride as the cocatalytic entities. High molecular weight polyoctenylene and polyheptenylene are obtained under bulk polymerization conditions. The scope of these classical metathesis catalysts in the polymerization of other hydrocarbon as well as functionalized dienes is studied, revealing significant reactivity differences with respect to the previously studied well-defined metathesis catalysts and providing insights into the identification of suitable classical systems for ADMET polymerization. References: 30