Abstract
A novel N,N′-[2,2′-bis(nitrilomethylidyne)]bis[α-methyl-4-(morpholin-1-ylmethyl)-6-tert-butyl phenolato]-1,2-diaminocyclohexane CoIII (2,4-dinitrophenoxy) complex (complex 1) was designed and used to couple carbon dioxide (CO2) and propylene oxide (PO) as a single-component catalyst. Systematic investigation revealed that complex 1 was highly active and selective in the coupling of CO2/PO and that complete consumption of PO was accomplished with high copolymer selectivity. A high molecular weight of up to 108.6 kg mol−1 was achieved with an appropriate combination of all variables. Matrix-assisted laser desorption ionization–time-of-flight mass spectrometer analysis implied that a chain-end control mechanism controls the copolymerization. In addition, complex 1 could operate very efficiently in the terpolymerization of PO and cyclohexene oxide (CHO) with CO2 to provide polycarbonates with a narrow polydispersity. The Tg of the PO/CHO/CO2 terpolymer can be easily adjusted between 40 and 118.9 °C.
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References
Darensbourg, D. J. & Holtcamp, M. W. Catalysts for the reactions of epoxides and carbon dioxide. Coord. Chem. Rev. 153, 155–174 (1996).
Super, M. & Beckman, E. J. Copolymerization of CO2 and cyclohexene oxide. Macromol. Symp. 127, 89–108 (1998).
Darensbourg, D. J., Mackiewicz, R. M., Phelps, A. L. & Billodeaux, D. R. Copolymerization of CO2 and epoxides catalyzed by metal salen complexes. Acc. Chem. Res. 37, 836–844 (2004).
Coates, G. W. & Moore, D. R. Discrete metal-based catalysts for the copolymerization of CO2 and epoxides: discovery, reactivity, optimization, and mechanism. Angew. Chem. Int. Ed. 43, 6618–6639 (2004).
Inoue, S., Koinuma, H. & Tsuruta, T. Copolymerization of carbon dioxide and epoxide. J. Polym. Sci. Part. B Polym. Lett. 7, 287–292 (1969a).
Inoue, S., Koinuma, H. & Tsurata, T. Copolymerization of carbon dioxide and epoxide with organometallic compounds. Makromol. Chem. 130, 210–220 (1969b).
Tan, C. S. & Hsu, T. J. Alternating copolymerization of carbon dioxide and propylene oxide with a rare-earth-metal coordination catalyst. Macromolecules 30, 3147–3150 (1997).
Darensbourg, D. J. & Phelps, A. L. Effective, selective coupling of propylene oxide and carbon dioxide to poly(propylene carbonate) using (salen)CrN3 catalysts. Inorg. Chem. 44, 4622–4629 (2005).
Darensbourg, D. J., Yarbrough, J. C., Ortiz, C. & Fang, C. C. Comparative kinetic studies of the copolymerization of cyclohexene oxide and propylene oxide with carbon dioxide in the presence of chromium salen derivatives. In situ FTIR measurements of copolymer vs cyclic carbonate production. J. Am. Chem. Soc. 125, 7586–7591 (2003).
Eberhardt, R., Allmendinger, M. & Rieger, B. DMAP/Cr(III) catalyst ratio: the decisive factor for poly(propylene carbonate) formation in the coupling of CO2 and propylene oxide. Macromol. Rapid Commun. 24, 194–196 (2003).
Cohen, C. T., Chu, T. & Coates, G. W. Cobalt catalysts for the alternating copolymerization of propylene oxide and carbon dioxide: combining high activity and selectivity. J. Am. Chem. Soc. 127, 10869–10878 (2005).
Sugimoto, H., Ohtsuka, H. & Inoue, S. Alternating copolymerization of carbon dioxide and epoxide catalyzed by an aluminum Schiff base-ammonium salt system. J. Polym. Sci. Part A Polym. Chem. 43, 4172–4186 (2005).
Qin, Z., Thomas, C. M., Lee, S. & Coates, G. W. Cobalt-based complexes for the copolymerization of propylene oxide and CO2: active and selective catalysts for polycarbonate synthesis. Angew. Chem. Int. Ed. 42, 5484–5487 (2003).
Allen, S. D., Moore, D. R., Lobkovsky, E. B. & Coates, G. W. High-activity, single-site catalysts for the alternating copolymerization of CO2 and oxide. J. Am. Chem. Soc. 124, 14284–14285 (2002).
Paddock, R. L. & Nguyen, S. T. Alternating copolymerization of CO2 and propylene oxide catalyzed by CoIII(salen)/Lewis base. Macromolecules 38, 6251–6253 (2005).
Lu, X. B. & Wang, Y. Highly active, binary catalyst systems for the alternating copolymerization of CO2 and epoxides under mild conditions. Angew. Chem. Int. Ed. 43, 3574–3577 (2004).
Lu, X. B., Lei, S., Wang, Y. M., Zhang, R., Zhang, Y. J., Peng, X. J., Zhang, Z. C. & Li, B. Design of highly active binary catalyst systems for CO2/epoxide copolymerization: polymer selectivity, enantioselectivity, and stereochemistry control. J. Am. Chem Soc. 128, 1664–1674 (2006).
Wang, J. T., Zhu, Q., Lu, X. L. & Meng, Y. Z. ZnGA–MMT catalyzed the copolymerization of carbon dioxide with propylene oxide. Eur. Polym. J. 41, 1108–1114 (2005).
Noh, E. K., Na, S. J., Sujith, S., Kim, S. W. & Lee, B. Y. Two components in a molecule: highly efficient and thermally robust catalytic system for CO2/epoxide copolymerization. J. Am. Chem. Soc. 129, 8082–8083 (2007).
Nakano, K., Kamada, T. & Nozaki, K. Selective formation of polycarbonate over cyclic carbonate: copolymerization of epoxides with carbon dioxide catalyzed by a cobalt(III) complex with a piperidinium end-capping arm. Angew. Chem. Int. Ed. 45, 7274–7277 (2006).
Liu, B. Y., Gao, Y. H., Zhao, X., Yan, W. D. & Wang, X. H. Alternating copolymerization of carbon dioxide and propylene oxide under bifunctional cobalt salen complexes: role of Lewis base substituent covalent bonded on salen ligand. J. Polym. Sci. Part A Polym. Chem. 48, 359–365 (2010).
Ren, W. M., Liu, Z. W., Wen, Y. Q., Zhang, R. & Lu, X. B. Mechanistic aspects of the copolymerization of CO2 with epoxides using a thermally stable single-site cobalt(III) catalyst. J. Am. Chem. Soc. 131, 11509–11518 (2009).
Niu, Y. S., Zhang, W. X., Pan, X., Chen, X. S., Zhuang, X. L. & Jing, X. B. Alternating copolymerization of carbon dioxide and propylene oxide catalyzed by (R,R)-salenCoIII(2,4-dinitrophenoxy) and Lewis-basic cocatalyst. J. Polym. Sci. Part A Polym. Chem. 45, 5050–5056 (2007).
DiMauro, E. F. & Kozlowski, M. C. Development of bifunctional salen catalysts: rapid, chemoselective alkylations of α-ketoesters. J. Am. Chem. Soc. 124, 12668–12669 (2002).
DiMauro, E. F. & Kozlowski, M. C. Salen-derived catalysts containing secondary basic groups in the addition of diethylzinc to aldehydes. Org. Lett. 19, 3053 (2001).
Niu, Y. S., Li, H. C., Chen, X. S., Zhang, W. X., Zhuang, X. L. & Jing, X. B. Alternating copolymerization of carbon dioxide and propylene oxide catalyzed by cobalt Schiff base complex. Macromol. Chem. Phys. 210, 1224–1229 (2009).
Zhuang, X. L., Oyaizu, K., Niu, Y. S., Koshika, K., Chen, X. S. & Nishide, H. Synthesis and electrochemistry of Schiff base cobalt(III) complexes and their catalytic activity for copolymerization of epoxide and carbon dioxide. Macromol. Chem. Phys. 211, 669–676 (2010).
Wisniewski, M., Le, B. A. & Spassky, N. Synthesis & properties of (D)-and (L)-lactide stereocopolymers using the system Achiral Schiff's base/Al methoxide as initiator. Macromol. Chem. Phys. 198, 1227–1238 (1997).
Le, B. A., Vincens, V., Jouglard, M. & Spassky, N. Ring-opening oligomerization reactions using aluminum complexes of schiff-bases as initiators. Makromol. Chem. Macromol. Symp. 73, 37–46 (1993).
Cohen, C. T. & Coates, G. W. Alternating copolymerization of propylene oxide and carbon dioxide with highly efficient and selective (salen)Co(III) catalysts: effect of ligand and cocatalyst variation. J. Polym. Sci. Part A Polym. Chem. 44, 5182–5191 (2006).
Hanton, S. D. Mass Spectrometry of polymers and polymer surfaces. Chem. Rev. 101, 527–570 (2001).
Schaus, S. E., Brandes, B. D., Larrow, J. F., Tokunaga, M., Hansen, K. B., Gould, A. E., Furrow, M. E. & Jacobsen, E. N. Highly selective hydrolytic kinetic resolution of terminal epoxides catalyzed by chiral (salen)CoIII complexes. practical synthesis of enantioenriched terminal epoxides and 1,2-diols. J. Am. Chem. Soc. 124, 1307–1315 (2002).
Shi, L., Lu, X. B., Zhang, R., Peng, X. J., Zhang, C. Q., Li, J. F. & Peng, X. M. Asymmetric alternating copolymerization and terpolymerization of epoxides with carbon dioxide at mild conditions. Macromolecules 39, 5679–5685 (2006).
Acknowledgements
We thank the Young Scientists Fund of the National Natural Science Foundation of China (Grant No. 51003051) and the High-level Talent Initial Funding for Scientific Research of Qingdao Agricultural University (Grant No. 630924) for financial support.
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Li, H., Niu, Y. Alternating copolymerization of CO2 with propylene oxide and terpolymerization with aliphatic epoxides by bifunctional cobalt Salen complex. Polym J 43, 121–125 (2011). https://doi.org/10.1038/pj.2010.112
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DOI: https://doi.org/10.1038/pj.2010.112
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