New Coordination Complexes Based on the 2,6-bis[1-(Phenylimino)ethyl] Pyridine Ligand: Effective Catalysts for the Synthesis of Propylene Carbonates from Carbon Dioxide and Epoxides
Abstract
:1. Introduction
2. Results and Discussion
2.1. Crystal Structures
2.2. Cycloaddition of CO2 and Propylene Oxide
2.3. Mechanism for the Cycloaddition Reaction of Propylene Oxide and CO2
3. Materials and Methods
3.1. Chemical Materials
3.2. X-ray Crystallographic Studies
3.3. Catalyst Characterization
3.4. Catalyst Preparation
3.4.1. Synthesis of the Ligand (2,6-bis[1-(Phenylimino)ethyl] pyridine) (L)
3.4.2. Synthesis of Complexes
3.4.3. Catalytic Procedure
3.5. Gaussian Calculation
4. Conclusions
Supplementary Materials
Author Contributions
Funding
Conflicts of Interest
References
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Sample Availability: All samples of the compounds are available from the authors. |
Compound | 1 | 2 | 3 |
---|---|---|---|
Empirical formula | C21H19Cl2CuN3 | C21H19Cl3CrN3 | C22H20.5Cl2MnN3.5 |
Formula weight | 447.83 | 471.74 | 459.76 |
Crystal system | Orthorhombic | Tetragonal | Triclinic |
Space group | Pbca | I41/a | P |
a (Å) | 15.632(8) | 15.775(4) | 8.988(3) |
b (Å) | 20.298(11) | 15.775(4) | 12.730(5) |
c (Å) | 25.070(13) | 33.247(8) | 20.143(7) |
α (°) | 90.00 | 90.00 | 80.318(8) |
β (°) | 90.00 | 90.00 | 79.252(7) |
γ (°) | 90.00 | 90.00 | 86.277(8) |
V (Å3) | 7955(7) | 8274(3) | 2230.7(14) |
Z | 16 | 16 | 4 |
ρcalcd (Mg·m−3) | 1.496 | 1.515 | 1.369 |
μ (mm−1) | 1.377 | 0.953 | 0.845 |
F(000) | 3664 | 3856 | 944 |
Crystal size (mm) | 0.35 × 0.28 × 0.21 | 0.33 × 0.26 × 0.14 | 0.31 × 0.24 × 0.13 |
θ range for data collection (°) | 2.31–18.37 | 1.43–25.10 | 2.07–25.10 |
Reflections collected | 38,290 | 20,559 | 11,205 |
Independent reflections | 7082 | 3688 | 7858 |
Rint | 0.1513 | 0.1302 | 0.0723 |
Final R indices [(I > 2σ(I)] | R1 = 0.0571 wR1 = 0.1052 | R1 = 0.0613 wR1 = 0.1305 | R1 = 0.0807 wR1 = 0.1638 |
R indices (all data) | R2 = 0.1291 wR2 = 0.1316 | R2 = 0.1296 wR2 = 0.1651 | R2 = 0.1985 wR2 = 0.2245 |
GOF | 0.958 | 1.011 | 0.951 |
1 | |||||
Cu1―N1 | 2.121(4) | Cu1―Cl2 | 2.3857(19) | N2―C13 | 1.335(6) |
Cu1―N2 | 1.950(5) | N1―C6 | 1.429(7) | N3―C14 | 1.277(6) |
Cu1―N3 | 2.078(4) | N1―C7 | 1.296(7) | N3―C16 | 1.434(6) |
Cu1―Cl1 | 2.2340(18) | N2―C9 | 1.337(6) | ||
Cu2―N4 | 2.107(4) | Cu2―Cl3 | 2.388(2) | N5―C34 | 1.324(6) |
Cu2―N5 | 1.936(4) | N4―C27 | 1.429(7) | N6―C35 | 1.277(6) |
Cu2―N6 | 2.086(4) | N4―C28 | 1.285(6) | N6―C37 | 1.435(6) |
Cu2―Cl4 | 2.2076(18) | N5―C30 | 1.344(7) | ||
N1―Cu1―N3 | 155.34(18) | N2―Cu1―N3 | 77.64(18) | N3―Cu1―Cl2 | 95.23(13) |
N1―Cu1―Cl1 | 100.62(13) | N2―Cu1―Cl1 | 141.29(13) | Cl1―Cu1―Cl2 | 109.23(7) |
N1―Cu1―Cl2 | 94.55(13) | N2―Cu1―Cl2 | 109.45(13) | ||
N2―Cu1―N1 | 77.76(18) | N3―Cu1―Cl1 | 97.41(13) | ||
N4―Cu2―N6 | 154.87(17) | N5―Cu2―N6 | 77.50(18) | N6―Cu2―Cl3 | 98.07(13) |
N4―Cu2―Cl4 | 101.51(13) | N5―Cu2―Cl4 | 149.59(14) | Cl4―Cu2―Cl3 | 106.88(7) |
N4―Cu2―Cl3 | 93.57(13) | N5―Cu2―Cl3 | 103.48(14) | ||
N5―Cu2―N4 | 78.17(19) | N6―Cu2―Cl4 | 96.31(13) | ||
2 | |||||
Cl1―Cr1 | 2.3002(19) | Cr1―N2 | 2.001(5) | N2―C8 | 1.333(7) |
Cl2―Cr1 | 2.3106(19) | Cr1―N3 | 2.111(5) | N2―C12 | 1.336(7) |
Cl3―Cr1 | 2.3239(19) | N1―C6 | 1.441(7) | N3―C13 | 1.295(7) |
Cr1―N1 | 2.109(5) | N1―C7 | 1.281(7) | N3―C14 | 1.448(7) |
N1―Cr1―N3 | 153.68(19) | N2―Cr1―N3 | 77.1(2) | N3―Cr1―Cl2 | 88.06(14) |
N1―Cr1―Cl1 | 100.10(14) | N2―Cr1―Cl1 | 176.62(16) | N3―Cr1―Cl3 | 89.96(14) |
N1―Cr1―Cl2 | 90.44(14) | N2―Cr1―Cl2 | 87.15(14) | Cl1―Cr1―Cl2 | 92.43(7) |
N1―Cr1―Cl3 | 89.14(14) | N2―Cr1―Cl3 | 87.58(14) | Cl1―Cr1―Cl3 | 92.88(7) |
N2―Cr1―N1 | 76.55(19) | N3―Cr1―Cl1 | 106.21(14) | Cl2―Cr1―Cl3 | 174.67(8) |
3 | |||||
Mn1―N1 | 2.186(6) | Mn1―Cl2 | 2.331(3) | N2―C7 | 1.278(10) |
Mn1―N2 | 2.297(7) | N1―C9 | 1.350(10) | N3―C14 | 1.290(9) |
Mn1―N3 | 2.303(7) | N1―C13 | 1.347(10) | N3―C16 | 1.417(8) |
Mn1―Cl1 | 2.337(3) | N2―C6 | 1.449(10) | ||
Mn2―N5 | 2.200(7) | Mn2―Cl3 | 2.341(3) | N4―C28 | 1.280(10) |
Mn2―N4 | 2.258(7) | N5―C30 | 1.352(10) | N6―C35 | 1.293(10) |
Mn2―N6 | 2.271(7) | N5―C34 | 1.324(10) | N6―C37 | 1.451(10) |
Mn2―Cl4 | 2.328(3) | N4―C27 | 1.445(10) | ||
N1―Mn1―N3 | 71.0(3) | N2―Mn1―N3 | 142.3(2) | N3―Mn1―Cl2 | 100.37(18) |
N1―Mn1―Cl1 | 116.29(10) | N2―Mn1―Cl1 | 99.24(19) | Cl1―Mn1―Cl2 | 118.28(10) |
N1―Mn1―Cl2 | 125.43(19) | N2―Mn1―Cl2 | 99.6(2) | ||
N2―Mn1―N1 | 71.3(3) | N3―Mn1―Cl1 | 98.97(18) | ||
N5―Mn2―N6 | 71.0(3) | N4―Mn2―N6 | 141.6(6) | N6―Mn2―Cl3 | 102.94(18) |
N5―Mn2―Cl4 | 116.26(18) | N4―Mn2―Cl4 | 97.37(4) | Cl4―Mn2―Cl3 | 116.91(11) |
N5―Mn2―Cl3 | 126.84(19) | N4―Mn2―Cl3 | 101.9(3) | ||
N4―Mn2―N5 | 70.3(3) | N6―Mn2―Cl4 | 96.89(4) |
Entry | Catalyst | Co-Catalyst | Conversion a (%) | TOF b (h−1) |
---|---|---|---|---|
1 | none | DMAP | 0 | 0 |
2 | 1 | DMAP | 43.1 | 216 |
3 | 2 | DMAP | 74.6 | 373 |
4 | 3 | DMAP | 62.3 | 312 |
5 | 2 | none | 0 | 0 |
6 | none | TBAB | 28.6 | 143 |
7 | 1 | TBAB | 40.8 | 204 |
8 | 2 | TBAB | 69.5 | 348 |
9 | 3 | TBAB | 61.4 | 307 |
Entry | [PO]/[2]/[DMAP] | P (MPa) | Time (h) | Temp (°C) | Conversion a (%) | TOF b (h−1) |
---|---|---|---|---|---|---|
1 | 1000:1:1 | 2.0 | 2 | 120 | 67.3 | 337 |
2 | 1000:1:1 | 2.5 | 2 | 120 | 74.6 | 373 |
3 | 1000:1:1 | 3.0 | 2 | 120 | 82.8 | 429 |
4 | 1000:1:1 | 3.5 | 2 | 120 | 84.2 | 421 |
5 | 2000:1:1 | 2.5 | 2 | 100 | 69.5 | 695 |
6 | 2000:1:1 | 2.5 | 3 | 100 | 83.1 | 554 |
7 | 2000:1:1 | 2.5 | 4 | 100 | 86.7 | 434 |
8 | 2000:1:1 | 2.5 | 2 | 120 | 62.2 | 622 |
9 | 2000:1:1 | 2.5 | 1 | 200 | 51.3 | 1026 |
10 | 2000:1:1 | 2.5 | 1 | 220 | 41.6 | 832 |
11 | 3000:1:1 | 2.5 | 2 | 120 | 25.4 | 381 |
12 | 4000:1:1 | 2.5 | 2 | 120 | 14.8 | 296 |
13 | 2000:1:2 | 2.5 | 2 | 120 | 72.3 | 723 |
14 | 2000:1:4 | 2.5 | 2 | 120 | 15.3 | 153 |
Complex | Metal Atom Charge Distribution | LUMO/eV | HOMO/eV | ΔE/eV |
---|---|---|---|---|
1 | 0.460 | −0.03090 | −0.24552 | 0.21463 |
2 | 0.454 | −0.15833 | −0.16290 | 0.00457 |
3 | 0.697 | −0.10583 | −0.22280 | 0.11697 |
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Xia, L.; Wang, W.-Z.; Liu, S.; Jia, X.-G.; Zhang, Y.-H.; Li, L.-L.; Wu, Y.; Su, B.-Y.; Geng, S.-B.; Fan, W. New Coordination Complexes Based on the 2,6-bis[1-(Phenylimino)ethyl] Pyridine Ligand: Effective Catalysts for the Synthesis of Propylene Carbonates from Carbon Dioxide and Epoxides. Molecules 2018, 23, 2304. https://doi.org/10.3390/molecules23092304
Xia L, Wang W-Z, Liu S, Jia X-G, Zhang Y-H, Li L-L, Wu Y, Su B-Y, Geng S-B, Fan W. New Coordination Complexes Based on the 2,6-bis[1-(Phenylimino)ethyl] Pyridine Ligand: Effective Catalysts for the Synthesis of Propylene Carbonates from Carbon Dioxide and Epoxides. Molecules. 2018; 23(9):2304. https://doi.org/10.3390/molecules23092304
Chicago/Turabian StyleXia, Li, Wen-Zhen Wang, Shuang Liu, Xin-Gang Jia, Ying-Hui Zhang, Lei-Lei Li, Ya Wu, Bi-Yun Su, Shu-Bo Geng, and Wei Fan. 2018. "New Coordination Complexes Based on the 2,6-bis[1-(Phenylimino)ethyl] Pyridine Ligand: Effective Catalysts for the Synthesis of Propylene Carbonates from Carbon Dioxide and Epoxides" Molecules 23, no. 9: 2304. https://doi.org/10.3390/molecules23092304