ABSTRACT
Conventional Metathesis Catalysts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 512 20.3.1 Polymerization of 5,5-Dimethylnorbornene. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 513 20.3.2 Polymerization of 1-Methylnorbornene . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 517 20.3.3 Polymerization of 7-Methylnorbornene and 7-Methylnorbornadiene . . . . . . . . . . . . 518 20.3.4 Polymers of Spiro(bicyclo[2.2.1]hept-2-ene-7,1′-cyclopropane) . . . . . . . . . . . . . . . . . 520 20.3.5 Polymers of Norbornene and Norbornadiene . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 520 20.3.6 Polymers of endo,exo-5,6-Dimethylnorbornene . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 522 20.3.7 Polymerization of endo-and exo-Dicyclopentadiene . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 523 20.3.8 Polymers of 2,3-Dicarboalkoxynorbornadienes and
2,3-Dicarboalkoxy-7-oxanorbornadienes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 523 20.3.9 Alternating Ethylene/Norbornene Copolymers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 524
20.4 Polymerizations with Well-Defined Metathesis Catalysts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 525 20.4.1 Titanacyclobutane Catalysts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 525 20.4.2 Tantalum-Based Catalysts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 527 20.4.3 Ruthenium Alkylidene Catalysts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 527 20.4.4 Tungsten-Based Catalysts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 528 20.4.5 Imido Molybdenum Alkylidene Complexes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 529
20.4.5.1 Cis/Trans Selectivity in Polymerizations Catalyzed by Imido Molybdenum Alkylidene Complexes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 530
20.4.5.2 Tacticity in Polymerizations Catalyzed by Imido Molybdenum Alkylidene Complexes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 536
20.4.6 Alternating Ethylene/Cyclopentene Copolymers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 544 20.4.7 Crystalline Poly(endo-dicyclopentadiene) and Hydrogenated
Poly(endo-dicyclopentadiene) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 545 20.5 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 545 References and Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 546
DK3712: “dk3712_c020” — 2007/10/10 — 14:09 — page 510 — #2
Over the last few decades, the olefin metathesis reaction has become a very important reaction in organic synthesis and polymer synthesis.1-7 It involves the transition metal-catalyzed redistribution of carbon-carbon double bonds. It can be understood as a reaction, in which the σ-and π-bonds of the C=C units are cleaved, and double bonds are reformed with the alkylidene groups exchanged (Scheme 20.1).
