Ring-opening metathesis polymerization of norbornene

Scheme 6. Ring-opening metathesis polymerization of norbornene in C02 [144,145]...

Fig. 4.16. Saturated versus unsaturated products from the Ziegler-Natta type polymerization and the ring-opening metathesis polymerization of norbornene.

Table 5. Relative rates of initiation and propagation in ring-opening metathesis polymerizations of norbornene in CgDs at 17-22 °C.

Ring-Opening Metathesis Polymerization of Norbornene Using an MTO Catalyst... 

The versatihty of these catalysts was further illustrated, when ring-opening metathesis polymerizations of norbornene were carried out in hquid carbon dioxide at high pressure, using Ru (H20)6-(Tos)2. The product was reported to be c/s-ditactic polynorbomene [172]. It should be noted, however, that stereoselective polymerizations of norbornene are not confined to these catalysts only. 

Delaude, L. Demonceau, A. Noels, A. F. Probing the stereoselectivity of the ruthenium-catalyzed ring-opening metathesis polymerization of norbornene and norbonadiene diesters. Macromolecules 2003, 36, 1446-1456. 

Mashima, K. Kaidzu, M. Tanaka, Y. Nakayama, Y Nakamura, A. Hamilton, J. G Rooney, J. J. Control of stereoselectivity in the ring-opening metathesis polymerization of norbornene by the auxiliary ligands butadiene and o-xylylene in well-defined pentamethylcyclopentadiene tantalum carbene complexes. Organometallics 1998,17,4183 195. 

Instead of a conventional polymerization reaction, Demonceau et al. [65] observed ring-opening metathesis polymerization of norbornene, which was initialized by ethyl diazoacetate or trimethyl-silyldiazomethane (Scheme 22.18). The used ruthenium complexes 62 and 63 gave moderate yields of the polymer (Figure 22.22, Table 22.27). 

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