Polymers of ε-Caprolactone Using New Copper(II) and Zinc(II) Complexes as Initiators: Synthesis, Characterization and X-Ray Crystal Structures
Abstract
:1. Introduction
2. Materials and Methods
2.1. Synthesis of Ligands
2.1.1. 4-Bromo-3,5-dimethylpyrazole (Br-Pz)
2.1.2. 4-Iodo-3,5-dimethylpyrazole (I-Pz)
2.1.3. 4-Nitro-3,5-dimethylpyrazole (NO2-Pz)
2.2. Synthesis of Complexes
2.2.1. [Zn(C6H5COO)2(Br-Pz)2] (1)
2.2.2. [Cu(C6H5COO)2(Br-Pz)2] (2)
2.2.3. [Zn(C6H5COO)2(I-Pz)2] (3)
2.2.4. [Cu(C6H5COO)2(I-Pz)2] (4)
2.2.5. [Zn(C6H5COO)2(NO2-Pz)2] (5)
2.2.6. [Cu(C6H5COO)2(NO2-Pz)2] (6)
2.3. X-ray Structural Determination
2.4. Polymerization of ε-Caprolactone
3. Results and Discussion
3.1. Synthesis and Characterization of Complexes 1–6
3.2. Mass Spectrometry and Elemental Analysis
3.3. Infrared and NMR Spectroscopy
3.4. Thermal Analysis
3.5. Single-Crystal X-ray Analysis
3.6. Polymerization of ε-Caprolactone
4. Conclusions
Supplementary Materials
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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Complex | Found, m/z | Assignment | Calculated, m/z |
---|---|---|---|
1 | 174.9893 | [C5H7BrN2 + H+]+ | 174.9865 |
2 | 174.9874 | [C5H7BrN2 + H+]+ | 174.9865 |
3 | 222.9815 | [C5H7IN2 + H+]+ | 222.9727 |
4 | 222.9857 | [C5H7IN2 + H+]+ | 222.9727 |
5 | 142.1591 | [C5H7N3O2 + H+]+ | 142.0611 |
6 | 142.0618 | [C5H7N3O2 + H+]+ | 142.0611 |
Complex | δH1-4 | δH7,8,12,13 | δH9,14 | δH5,6,10,11 |
---|---|---|---|---|
1 | 2.28 (11.65) | 7.40 (4.01) | 7.48 (2.02) | 8.12 (4.02) |
3 | 2.12 (11.66) | 7.45 (4.18) | 7.51 (1.90) | 7.98 (3.96) |
5 | 2.12 (11.67) | 7.43 (3.91) | 7.51 (2.09) | 7.96 (4.07) |
Complex | 1 | 4 |
---|---|---|
Chemical Formula | C24H24Br2N4O4Zn | C24H24I2N4O4Cu |
Mr | 657.66 | 749.82 |
Crystalline System | Triclinic | Tetragonal |
Spatial Group | P-1 | I41/a |
Temperature (K) | 298(2) | 298(2) |
a, b, c (Å)/a, c (Å) | 11.5022(19), 11.706(2), 12.459(2) | 31.5581(18), 5.5116(9) |
α, β, γ (°) | 111.470(15), 101.888(14), 111.795(16) | 90, 90, 90 |
V (Å3) | 1331.3(4) | 5489.1(11) |
Z | 2 | 8 |
Type of Radiation | MoKα | MoKα |
µ (mm−1) | 3.96 | 3.08 |
Crystal Size (mm) | 0.38 × 0.29 × 0.21 | 0.21 × 0.12 × 0.09 |
Tmin, Tmax | 0.871, 1.000 | 0.408, 1.000 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 153.37, 5600, 4030 | 29.200, 3012, 2206 |
Rint | 0.059 | 0.076 |
(sin θ/λ)max (Å−1) | 0.641 | 0.641 |
R[F2> 2σ(F2)], wR(F2), S | 0.049, 0.136, 1.05 | 0.061, 0.193, 1.08 |
No. of reflections | 5600 | 3012 |
No. of parameters | 320 | 172 |
No. of restraints | 13 | 69 |
H-atom treatment | H-atom parameters constrained | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.77, −0.89 | 1.81, −0.74 |
Polymer | % Yield | Time (h) a | Melting Point b (°C) | TC (°C) | Crystallinity c (°C) | TD (°C) |
---|---|---|---|---|---|---|
PCL1 | 99.0 | 26 | 59.9 | 32.8 | 74.4 | 285 |
PCL2 | 96.3 | 29 | 61.5 | 38.7 | 78.6 | 277 |
PCL3 | 99.6 | 25 | 60.1 | 33.1 | 72.2 | 261 |
PCL4 | 95.8 | 28 | 60.3 | 33.4 | 72.8 | 273 |
PCL5 | 92.1 | 28 | 59.9 | 30.6 | 70.2 | 268 |
Polymer | Mn | MW (Da) | PDI a |
---|---|---|---|
PCL1 | 32,688 | 38,762 | 1.19 |
PCL2 | 31,647 | 37,146 | 1.17 |
PCL3 | 30,946 | 36,583 | 1.18 |
PCL4 | 31,770 | 37,763 | 1.19 |
PCL5 | 17,932 | 22,973 | 1.28 |
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Posada, A.F.; Macías, M.A.; Movilla, S.; Miscione, G.P.; Pérez, L.D.; Hurtado, J.J. Polymers of ε-Caprolactone Using New Copper(II) and Zinc(II) Complexes as Initiators: Synthesis, Characterization and X-Ray Crystal Structures. Polymers 2018, 10, 1239. https://doi.org/10.3390/polym10111239
Posada AF, Macías MA, Movilla S, Miscione GP, Pérez LD, Hurtado JJ. Polymers of ε-Caprolactone Using New Copper(II) and Zinc(II) Complexes as Initiators: Synthesis, Characterization and X-Ray Crystal Structures. Polymers. 2018; 10(11):1239. https://doi.org/10.3390/polym10111239
Chicago/Turabian StylePosada, Andrés F., Mario A. Macías, Santiago Movilla, Gian Pietro Miscione, León D. Pérez, and John J. Hurtado. 2018. "Polymers of ε-Caprolactone Using New Copper(II) and Zinc(II) Complexes as Initiators: Synthesis, Characterization and X-Ray Crystal Structures" Polymers 10, no. 11: 1239. https://doi.org/10.3390/polym10111239
APA StylePosada, A. F., Macías, M. A., Movilla, S., Miscione, G. P., Pérez, L. D., & Hurtado, J. J. (2018). Polymers of ε-Caprolactone Using New Copper(II) and Zinc(II) Complexes as Initiators: Synthesis, Characterization and X-Ray Crystal Structures. Polymers, 10(11), 1239. https://doi.org/10.3390/polym10111239