Table 1. Polymerization of DCMNBD with Initiators 4a–h in CDCl3a.
| imido substituent | kobs (M–1 s–1) | polymer structurec |
|---|---|---|
| 2,4,6-Cl3C6H2 (4a) | 0.59 | 84% cis,iso |
| 2,4,6-Br3C6H2 (4b) | 0.075 | 71% cis,iso |
| 2,6-Cl2-4-(CF3)C6H2 (4c) | 1.1 | 85% cis,iso |
| 3,5-(CF3)2C6H3 (4d) | >4.1 (est)b | 53% cis,iso |
| 2,6-Cl2C6H3 (4e) | 0.51 | 88% cis,iso |
| C6F5 (4f) | >4.1 (est)b | 85% cis,iso |
| 2,6-Me2C6H3 (4g) | 0.005 | 75% cis,iso (10% trans) |
| 3,5-Me2C6H3 (4h) | >4.1 (est)b | 55% cis,iso |
a
Monomer and initiator concentrations were held constant at 0.002 and 0.1 M, respectively, across three trials for each initiator.
b
Reactions were >95% complete within 5 min.
c
Unless otherwise noted, <5% trans polymer sequences is observed.