ROP of ε-CL catalysed by complexes 1 and 2.
| ||||||||
|---|---|---|---|---|---|---|---|---|
| Entry | Catalyst | Temperature | Time (h) | Conversiona (%) | M n (kDa) | Đ c | Initiation efficiencyd (%) | |
| Calculatedb | Observedc | |||||||
| 1 | 1 | RT | 24 | 6 | — | — | — | — |
| 2 | 1 | 60 °C | 1 | 64 | 7.4 | 58.8 | 1.10 | 12.4 |
| 3 | 1 | 60 °C | 4 | 97 | 11.1 | 121.1 | 2.24 | 9.1 |
| 4e | Pyridone | 60 °C | 4 | 0 | — | — | — | — |
| 5 | 2 | 60 °C | 1 | >99 | 11.4 | 77.6 | 1.48 | 14.7 |
| 6 | 2 | RT | 1 | 2 | 0.2 | 9.5 | — | 2.5 |
| 7 | 2 | RT | 2 | 10 | 1.1 | 25.4 | 1.41 | 4.7 |
| 8 | 2 | RT | 4 | 43 | 4.9 | 45.8 | 1.47 | 11.2 |
| 9e | Me-pyridone | RT | 4 | 0 | — | — | — | — |
| 10f | 2 | RT | 1 | 0 | — | — | — | — |
| 11f | 2 | RT | 4 | 17 | 2.0 | 22.8 | 1.23 | 9.1 |
| 12f | 2 | RT | 23 | 81 | 9.3 | 51.0 | 1.32 | 19.1 |
a
Conversion was calculated ex situ by 1H NMR spectroscopy.
b
M n calc of polymers calculated from monomer conversion; Mn calc = ([ε-CL]0/[Cat]0) × (% conversion of ε-CL) × 114.14, assuming 1 polymer chain per catalyst centre.
c
M n obs and Đ determined by size exclusion chromatography (SEC) using polystyrene standards in THF: values were corrected using a correction factor (0.56).37
d
Calculated according to eqn (S1)–(S3).†
e
Zinc free control reaction with the respective pyridone substrate.
f
Performed in THF rather than toluene.