TY - JOUR
TI - Metathesis Polymerization Reactions Induced by the Bimetallic Complex (Ph4P)2[W2(μ-Br)3Br6]
AU - Despoina Chriti
AU - Alexios Grigoropoulos
AU - Grigorios Raptopoulos
AU - Georgios Charalambidis
AU - Vasilis Nikolaou
AU - Athanassios G. Coutsolelos
AU - Marinos Pitsikalis
AU - Konstantinos Mertis
AU - Patrina Paraskevopoulou
JO - Polymers
PY - 2015
VL - 7
TODO - 12
SP - 2611-2624
PB - MDPI
SN - 2073-4360
TODO - null
TODO - metathesis, ROMP, metal-metal bonds, tungsten
TODO - The reactivity of the bimetallic complex (Ph4P)2[W2(μ-Br)3Br6] ({W2.5W}7+, a'2e3) towards ring opening metathesis polymerization (ROMP) of norbornene (NBE) and some of its derivatives, as well as the mechanistically related metathesis polymerization of phenylacetylene (PA), is presented. Our results show that addition of a silver salt (AgBF4) is necessary for the activation of the ditungsten complex. Polymerization of PA proceeds smoothly in tetrahydrofuran (THF) producing polyphenylacetylene (PPA) in high yields. On the other hand, the ROMP of NBE and its derivatives is more efficient in CH2Cl2, providing high yields of polymers. 13C Cross Polarization Magic  Angle Spinning (CPMAS) spectra of insoluble polynorbornadiene (PNBD) and polydicyclopentadiene (PDCPD) revealed the operation of two mechanisms (metathetic and radical) for cross-linking, with the metathesis pathway prevailing.
ER -