Table 1. ROCOP of CO2/PO of Catalysts 1–4a.
| # | Co(III)/M(I) | time (h) | conv. (%)b | CO2 (%)c | polym. (%)d | TONe | TOF (h–1)f | kp (mM–1 s–1)g | Mn [Đ] (g mol–1)h |
|---|---|---|---|---|---|---|---|---|---|
| 1 | Na = 1 | 5.0 | 15 | >99 | 79 | 600 | 120 | 2.09 | 2300 [1.08] |
| 2 | K = 2 | 4.0 | 34 | >99 | 98 | 1360 | 340 | 11.20 | 5900 [1.10] |
| 3i | K = 2 | 1.4 | 28 | >99 | 93 | 1120 | 800 | 24.0 | 5800 [1.07] |
| 4j | K = 2 | 19.8 | 90 | >99 | 98 | 1800 | 91 | 10.70 | 8800 [1.04] |
| 5 | Rb = 3 | 23 | 31 | >99 | 91 | 1240 | 54 | 1.77 | 6500 [1.07] |
| 6 | Cs = 4 | 23 | 27 | >99 | 84 | 1080 | 47 | 1.76 | 5600 [1.08] |
| 7k,13 | [(salen)Co(2,4-DNP)]/18C6/KI | 3.0 | 27 | >99 | 41 | 540 | 182 | – | 4700 [1.43] |
| 8l,26 | [(salcy)Co(O2CCF3)]PPN(O2CCF3) (20 equiv H2O) | 48 | 95 | >99 | >99 | 475 | 10 | – | 7800 [1.06] |
| 9m,18 | [(salen[Pip+]2)Co(OAc)2] (20 equiv MeOH) | 20 | 95 | >99 | 96 | 960 | 48 | – | 5100 [1.06] |
| 10n,27 | [(salen[NBu3+]4)Co(OAc)](NO2)4 (400 equiv adipic acid) | 1 | 10 | >99 | >99 | 10 300 | 10 300 | – | 2600 [1.05] |
| 11o,31 | Et3B:[NBu4+]2[O3C2–] | 14 | 95 | 91 | 95 | 37 | 3 | – | 4100 [1.10] |
| 12p,59 | Zn-Co-DMCC (15 equiv sebacic acid) | 30 | 64 | 75 | 98 | 1280 g/g | 43 g/g/h | – | 1500 [1.10] |
Reaction conditions: Catalyst (0.025 mol %, 3.5 mM), PO (6 mL, 14 M), 1,2-cyclohexanediol (0.5 mol %, 70 mM), 20 bar CO2, 50 °C.
PO conversion determined from the relative integrals in the 1H NMR spectrum of PPC (4.92 ppm, 1H), PC (4.77 ppm, 1H), and PPO (3.46–3.64 ppm, 3H) using mesitylene as an internal standard (6.70 ppm).
CO2 selectivity determined by the relative integrals in the 1H NMR spectrum of PPC (4.92 ppm, 1H) and PC (4.77 ppm, 1H) compared with PPO (3.46–3.64 ppm, 3H).
Polymer selectivity determined by the relative integrals in the 1H NMR spectra of PPC (4.92 ppm, 1H) against PC (4.77 ppm, 1H).
Turnover number (TON) = number of moles of PO consumed/number of moles catalyst.
Turnover frequency (TOF) = TON/time (h).
kp = kobs/[cat]1; kobs determined as the gradient of the plot of ln[PO]t/[PO]0 vs time.
Determined by GPC analysis, in THF, calibrated with narrow-Mn polystyrene standards; dispersity values in parentheses.
Catalyst (0.025 mol %, 3.5 mM), PO (6 mL, 14 M), 1,2-cyclohexanediol (0.5 mol %, 70 mM), 30 bar CO2, 70 °C.
Catalyst (0.05 mol %, 3.5 mM), PO (3 mL, 7 M), diethyl carbonate (3 mL), 1,2-cyclohexanediol (0.5 mol %, 70 mM), 20 bar CO2, 50 °C.
Catalyst (0.05 mol %, 7.1 mM), PO (14 mL, 14 M), KI (0.05 mol %, 7.1 mM), 15 bar CO2, 25 °C.
Catalyst (0.2 mol %, 10.0 mM), PO (0.5 mL, 4.6 M), toluene/chloroform (1 mL), PPNX (0.2 mol %, 10.0 mM), H2O (2.0 mol %, 1 M), 15 bar CO2, 25 °C.
Catalyst (0.1 mol %, 7.2 mM), PO (1 mL, 7 M), 1,2-dimethoxyethane (1 mL), methanol (1.0 mol %, 0.14 M), 14 bar CO2, 25 °C.
Catalyst (0.001 mol %, 1.7 μM), PO (12 mL, 14 M), adipic acid (0.4 mol %, 0.68 M), 25 bar CO2, 75 °C.
Catalyst (7.5 mol %, 0.25 M, 1 mL from a 1 M THF solution), tetra-butyl ammonium carbonate (TBAC) (2.5 mol %, 0.09 M), PO (2 mL, 7 M), THF (1 mL), 10 bar CO2, 40 °C.
Catalyst (50 mg), PO (100 mL, 14 M), sebacic acid (95 mmol, 0.95 M), 40 bar CO2, 50 °C. For illustrations of the literature catalyst structures, see Figure S15.