Enhancement on Nickel-Mediated Ethylene Polymerization by Concerted Steric Hindrance and Fluorine Effect
Received date: 2022-02-10
Online published: 2022-03-23
Supported by
National Natural Science Foundation of China(22122110); Education Department of Jilin Province(JJKH20210728KJ)
Olefin polymerization is one of the most important chemical reactions in industry. Transition metal catalysts are the key to the development of olefin polymerization. Neutral salicylaldiminato nickel catalyst stands out due to the nature of both functional-group tolerance and cocatalyst-free. Either sterically hindered effect or fluorine effect has extensively been reported over the past decades to improve properties of neutral and single-component salicylaldiminato nickel catalyst; however, combination of these two effects to generate a concerted strategy is much less studied. In this work, both para-sterically hindered substituents including phenyl, 1-naphthyl or 9-anthracenyl group and ortho-fluorine substituents are concurrently installed into salicylaldimine ligands, and thus five salicylaldiminato nickel catalysts have been synthesized and fully identified by 1H and 13C NMR spectroscopy, elemental analysis and X-ray diffraction technique if possible. Without the addition of any activator, these single-component nickel catalysts are used to ethylene polymerization. Influence of sterically hindered effect, fluorine effect, reaction temperature and reaction time on catalytic activity, polymer molecular weight, and branching density of polymer is comprehensively investigated. ortho-Fluorine substituents particularly elevate catalytic activity, lifetime of catalyst species, and polymer molecular weight, while decreases branching density of polymer. Enhancement of catalytic activity and polymer molecular weight reaches two orders of magnitude and 36 times, respectively; and linear structure (5 branches/1000 carbon) of polyethylene can be accessible. This should originate from the inhibition of both chain transfer and chain walking pathways. The bulk of para-sterically hindered substituents can be designed according to the required catalytic activity and molecular weight, and notably it has a minor influence on branching density of polymer. The concerted combination of fluorine effect and steric shielding effect enables the formation of linear ultrahigh molecular weight polyethylene (UHMWPE). This work develops a new strategy for the efficient design of salicylaldiminato nickel olefin polymerization catalyst.
Yuyin Wang , Xiaoqiang Hu , Hongliang Mu , Yan Xia , Yue Chi , Zhongbao Jian . Enhancement on Nickel-Mediated Ethylene Polymerization by Concerted Steric Hindrance and Fluorine Effect[J]. Acta Chimica Sinica, 2022 , 80(6) : 741 -747 . DOI: 10.6023/A22020066
[1] | Johnson, L. K.; Killian, C. M.; Brookhart, M. J. Am. Chem. Soc. 1995, 117, 6414. |
[2] | Younkin, T. R.; Connor, E. F.; Henderson, J. I.; Friedrich, S. K.; Grubbs, R. H.; Bansleben, D. A. Science 2000, 287, 460. |
[3] | Mu, H.; Zhou, G.; Hu, X.; Jian, Z. Coord. Chem. Rev. 2021, 435, 213802. |
[4] | Mu, H.; Pan, L.; Song, D.; Li, Y. Chem. Rev. 2015, 115, 12091. |
[5] | Redshaw, C.; Tang, Y. Chem. Soc. Rev. 2012, 41, 4484. |
[6] | Tan, C, Chen. C.; Angew. Chem., Int. Ed. 2019, 58, 7192. |
[7] | Mecking, S.; Schnitte, M. Acc Chem. Res. 2020, 53, 2738. |
[8] | Jian, Z. Acta Polym. Sin. 2018, (11), 1359. (in Chinese) |
[8] | (简忠保, 高分子学报, 2018, (11), 1359.) |
[9] | Chen, M.; Chen, C. Acta Polym. Sin. 2018, (11), 1372. (in Chinese) |
[9] | (陈敏, 陈昶乐, 高分子学报, 2018, (11), 1372.) |
[10] | Li, Y.; Wang, X.; Tang, Y. Acta Chim. Sinica 2021, 79, 1320. (in Chinese) |
[10] | (李勇, 王晓艳, 唐勇, 化学学报, 2021, 79, 1320.) |
[11] | Liu, G.; Huang, Z. Chin. J. Chem. 2020, 38, 1445. |
[12] | Hu, X.; Zhang, Y.; Li, B.; Jian, Z. Chin. J. Chem. 2021, 39, 2829. |
[13] | Zhang, Y.; Kang, X.; Jian, Z. Nat. Commun. 2022, 13, 725. |
[14] | Wang, C.; Kang, X.; Dai, S.; Cui, F.; Li, Y.; Mu, H.; Mecking, S.; Jian, Z. Angew. Chem., Int. Ed. 2021, 60, 4018. |
[15] | Li, Q.; Wang, C.; Mu, H.; Jian, Z. J. Catal. 2021, 400, 332. |
[16] | Chen, Z.; Mesgar, M.; White, P. S.; Daugulis, O.; Brookhart, M. ACS Catal. 2015, 5, 631. |
[17] | Bastero, A.; Göttker-Schnetmann, I.; Röhr, C.; Mecking, S. Adv. Synth. Catal. 2007, 349, 2307. |
[18] | Göttker-Schnetmann, I.; Wehrmann, P.; Röhr, C.; Mecking, S. Organometallics 2007, 26, 2348. |
[19] | Osichow, A.; Göttker-Schnetmann, I.; Mecking, S. Organometallic 2013, 32, 5239. |
[20] | Schnitte, M.; Staiger, A.; Casper, L. A.; Mecking, S. Nat. Commun. 2019, 10, 2592. |
[21] | Zuideveld, M. A.; Wehrmann, P.; Röhr, C.; Mecking, S. Angew. Chem., Int. Ed. 2004, 43, 869. |
[22] | Wiedemann, T.; Voit, G.; Tchernook, A.; Roesle, P.; Göttker- Schnetmann, I.; Mecking, S. J. Am. Chem. Soc. 2014, 136, 2078. |
[23] | Göttker-Schnetmann, I.; Korthals, B.; Mecking, S. J. Am. Chem. Soc. 2006, 128, 7708. |
[24] | Korthals, B.; Göttker-Schnetmann, I.; Mecking, S. Organometallics 2007, 26, 1311. |
[25] | Schnitte, M.; Scholliers, J. S.; Riedmiller, K.; Mecking, S. Angew. Chem., Int. Ed. 2020, 59, 3258. |
[26] | Bastero, A.; Francio, G.; Leitner, W.; Mecking, S. Chem. Eur. J. 2006, 12, 6110. |
[27] | Guironnet, D.; Friedberger, T.; Mecking, S. Dalton Trans. 2009, 41, 8929. |
[28] | Cai, Z.; Do, L. H. Organometallics 2017, 36, 4691. |
[29] | Cai, Z.; Xiao, D.; Do, L. H. J. Am. Chem. Soc. 2015, 137, 15501. |
[30] | Tran, T. V.; Nguyen, Y. H.; Do, L. H. Polym. Chem. 2019, 10, 3718. |
[31] | Stephenson, C. J.; McInnis, J. P.; Chen, C.; Weberski, M. P.; Motta, A.; Delferro, M.; Marks, T. J. ACS. Catal. 2014, 4, 999. |
[32] | Delferro, M.; McInnis, J. P.; Marks, T. J. Organometallics 2010, 29, 5040. |
[33] | Hu, T.; Li, Y.; Liu, J.; Li, Y. Organometallics 2007, 26, 2609. |
[34] | Makio, H.; Terao, H.; Iwashita, A.; Fujita, T. Chem. Rev. 2011, 111, 2363. |
[35] | Tian, J.; Hustad, P. D.; Coates, G. W. J. Am. Chem. Soc. 2001, 123, 5134. |
[36] | Hu, X.; Kang, X.; Jian, Z. CCS. Chem. 2021, 3, 1598. |
[37] | Cui, L.; Hu, X.; Zhang, Y.; Jian, Z. Acta Polym. Sin. 2021, 52, 531. (in Chinese) |
[37] | (崔磊, 胡小强, 张燚鑫, 简忠保, 高分子学报, 2021, 52, 531.) |
[38] | Mitani, M.; Furuyama, R.; Mohri, J.; Saito, J.; Ishii, S.; Terao, H.; Nakano, T.; Tanaka, H.; Fujita, T. J. Am. Chem. Soc. 2003, 125, 4293. |
[39] | Mitani, M,.; Mohri, J.; Yoshida, Y.; Saito, J.; Ishii, S.; Tsuru, K.; Matsui, S.; Furuyama, R.; Nakano, T.; Tanaka, H.; Kojoh, S.; Matsugi, T.; Kashiwa, N.; Fujita, T. J. Am. Chem. Soc. 2002, 124, 3327. |
[40] | Saito, J.; Mitani, M.; Mohri, J. I.; Yoshida, Y.; Matsui, S.; Ishii, S. I.; Kojoh, S. I.; Kashiwa, N.; Fujita, T. Angew. Chem., Int. Ed. 2001, 40, 2918. |
[41] | Yu, S. M.; Mecking, S. J. Am. Chem. Soc. 2008, 130, 13204. |
[42] | Hu, X.; Zhang, Y.; Li, B.; Jian, Z. Chem. Eur. J. 2021, 27, 11935. |
[43] | Popeney, C. S.; Rheingold, A. L.; Guan, Z. Organometallics 2009, 28, 4452. |
[44] | Weberski, M. P.; Chen, C.; Delferro, M.; Zuccaccia, C.; Macchioni, A.; Marks, T. J. Organometallics 2012, 31, 3773. |
[45] | Wang, J.; Yao, E.; Chen, Z.; Ma, Y. Macromolecules 2015, 48, 5504. |
[46] | Kaschube, W.; Pörschke, K. R.; Wilke, G. J. Organomet. Chem. 1988, 355, 525. |
[47] | Jones, D. J.; Gibson, V. C.; Green, S. M.; Maddox, P. J.; White, A. J.; Williams, D. J. J. Am. Chem. Soc. 2005, 127, 11037. |
/
〈 |
|
〉 |