- Email: [email protected]
132 PI catalysts: New titanium complexes having two pyrrolide-imine chelate ligands for olefin polymerization
521
Science and Technology in Catalysis 2002
Copyright 9 2003 by Kodansha Ltd.
132 Pl Catalysts: New Titanium Complexes Having Two Pyrrolide-lmine Chelate Ligands for Olefin Polymerization Yasunori YOSHIDA, ~ Shigekazu MATSUI, ] Yukihiro TAKAGI, ~ Makoto MITANI, ~ Junji SAITO, ~ Sei-ichi ISHII, ] Takashi NAKANO, ~ Hidetsugu TANAKA, ~ Norio KASHIWA, and Terunori FUJITA ~ tR&D Center, Mitsui Chemicals, Inc.,580-32 Nagaura, Sodegaura, Chiba 299-0265 Japan
I. INTRODUCTION After the sensational discovery of group 4 metallocene complex catalysts, well-defined transition metal complexes have been actively investigated as olefin polymerization catalysts in an effort to create post-metailocene catalysts. As a result, recently, quite a few high performance new olefin polymerization catalysts based on both early and late transition metal complexes have been developed [1, 2]. In our own efforts, we have recently acquired, as a result of ligand-oriented catalyst design research, a series of transition metal complexes featuring non-symmetric bidentate ligand(s) (e.g., phenoxy-imine, phenoxy-pyridine, indolide-imine, and imine-phenoxy ligand(s)) which exhibit high catalytic performance for olefin polymerization including living olefin polymerization [3-7]. In this paper, we would like to introduce new titanium complexes bearing two pyrrolide-imine chelate ligands, named PI Catalysts (Fig. 1)[8, 9].
~ H ~
iCI2 Complex1: X9 Phenyq Complex 2: X9 ~*~lohexyl coml~x 3: x = Cy:k)oc~
Fig.l. PI Catalysts
2. RESULT AND DISCUSSION New bis(pyrrolyl-2-aldiminato) titanium complexes, named PI Catalysts, were prepared from the lithium salt of the corresponding ligands and TiCI4, and their molecular structures were established by X-ray analyses. Prototype PI Catalyst, complex 1 adopts a distorted octahedral geometry around the Ti center, thus, the two pyrrole nitrogen atoms are situated in trans position, while the two imine nitrogen and the two chlorine atoms are oriented cis to each other at the central titanium. The results of DFT calculations on a
522 Y. Yoshida et aL methyl cationic complex generated from complex 1, an initial active species formed by MAO for olefin polymerization, indicate that the cationic complex has cis-located active sites (A methyl group and a coordinated ethylene are in a cis configuration). These results together with X-ray analysis suggest that complex 1 has a high potential for olefin polymerization. PI Catalysts displayed high ethylene polymerization activities using MAO as a cocatalyst. The activity increased dramatically by introducing a bulky X substituent. One of the complexes (complex 3: possessing a cyclooctyl group at the X position) exhibited a very high activity (33200 kg-PE.mol-Ti-l'h-~) with a very high molecular weight value (My: 317.0 • 104). This activity value, 33200 kg-PE'mol-Ti-~'h-~, is higher than that of Cp2TiCI: under idintical conditions. Ethylene / norbornene copolymerizations were carried out with complex 1 or 2 using MAO as a cocatalyst. Complexes 1 and 2 displayed high activities (complex 1:0.58 kgPolymer.mol-Ti-~.h-~, complex 2:2.73 kg-Polymer.mol-Ti-~'h-~) and produced amorphous polymers. Microstructural analyses using ~3C-NMR spectroscopy suggest that the polymers are ethylene / norbornene copolymers produced via addition polymerization, with norbornene contents of 48.6 mol% (complex 1) and 44.5 mol% (complex 2). GPC analyses revealed that the copolymers have extremely narrow molecular weight distributions (MJMn < 1.25), which suggest that complexes 1 and 2 may have the characteristics of a living ethylene / norbornene copolymerization. Mn increased (>800000) proportionally with the polymerization time (20 min) while the narrow MJMn was retained for each case, which indicates that the copolymerization is living. In conclusion, the catalytic behavior of Ti complexes with two pyrrolide-imine chelate ligands, PI Catalysts, has been introduced. The results summarized herein indicate that titanium complexes possessing two pyrrolide-imine chelate ligands, PI Catalysts, have great potential as high performance new olefin polymerization catalysts. References [1] G. J. P. Biritovsek, V. C. Gibson, D. F. Wass, Angew. Chem., int. Ed. Engl., 38, (1999) 428. [2] S. D. Ittel, L. K Johnson, M. Brookhart, Chem. Rev., 100, (2000) 1169. [3] S. Matsui, M. Mitani, J. Saito, Y. Tohi, H. Makio, N. Matsukawa, Y. Takagi, K. TstmJ, M. Nitabaru, T. Nakano, H. Tanaka, N. Kashiwa, and T. Fujita, J. Am. Chem. Soc., 123, (2001) 6847. [4] M. Mitani, 1~ Furuyama, J. Mohri, J. Saito, S. Ishii, H. Terao, N. Kashiwa, and T. Fujita, J. Am. Chem. Soc., 124, (2002) 7888. [5] H. Makio, N. Kashiwa, and T. Fujita, Adv. Synth. Catal., 344, (2002) 1. Y. Inoue, T. Nakano, H. Tanaka, N. Kashiwa, and T. Fujita, Chem. Lett., 2001, 1060. [6] T. Matsugi, S. Matsui, S. Kojoh, Y. Takagi, Y. Inoue, T. Nakano, T. Fujita, and N. Kashiwa, Macromolecules, 35, (2002) 4880. [7] Y. Suzuki, N. Kashiwa, and T. Fujita, Chem. Lett., 2002, 358. [8] Y. Yoshida, S. Matsui, Y. Takagi, M. Mitani, M. Nitabaru, T. Nakano, H. Tanaka, and T. Fujita, Organometallics, 20, (2001) 4793. [9] Y. Yoshida, J. Saito, M. Mitani, Y. Takagi, S. Matsui, S. Ishii, Y. Nakano, N. Kashiwa, and T. Fujita, Chem. Commun., 2002, 1298.
Science and Technology in Catalysis 2002
Copyright 9 2003 by Kodansha Ltd.
132 Pl Catalysts: New Titanium Complexes Having Two Pyrrolide-lmine Chelate Ligands for Olefin Polymerization Yasunori YOSHIDA, ~ Shigekazu MATSUI, ] Yukihiro TAKAGI, ~ Makoto MITANI, ~ Junji SAITO, ~ Sei-ichi ISHII, ] Takashi NAKANO, ~ Hidetsugu TANAKA, ~ Norio KASHIWA, and Terunori FUJITA ~ tR&D Center, Mitsui Chemicals, Inc.,580-32 Nagaura, Sodegaura, Chiba 299-0265 Japan
I. INTRODUCTION After the sensational discovery of group 4 metallocene complex catalysts, well-defined transition metal complexes have been actively investigated as olefin polymerization catalysts in an effort to create post-metailocene catalysts. As a result, recently, quite a few high performance new olefin polymerization catalysts based on both early and late transition metal complexes have been developed [1, 2]. In our own efforts, we have recently acquired, as a result of ligand-oriented catalyst design research, a series of transition metal complexes featuring non-symmetric bidentate ligand(s) (e.g., phenoxy-imine, phenoxy-pyridine, indolide-imine, and imine-phenoxy ligand(s)) which exhibit high catalytic performance for olefin polymerization including living olefin polymerization [3-7]. In this paper, we would like to introduce new titanium complexes bearing two pyrrolide-imine chelate ligands, named PI Catalysts (Fig. 1)[8, 9].
~ H ~
iCI2 Complex1: X9 Phenyq Complex 2: X9 ~*~lohexyl coml~x 3: x = Cy:k)oc~
Fig.l. PI Catalysts
2. RESULT AND DISCUSSION New bis(pyrrolyl-2-aldiminato) titanium complexes, named PI Catalysts, were prepared from the lithium salt of the corresponding ligands and TiCI4, and their molecular structures were established by X-ray analyses. Prototype PI Catalyst, complex 1 adopts a distorted octahedral geometry around the Ti center, thus, the two pyrrole nitrogen atoms are situated in trans position, while the two imine nitrogen and the two chlorine atoms are oriented cis to each other at the central titanium. The results of DFT calculations on a
522 Y. Yoshida et aL methyl cationic complex generated from complex 1, an initial active species formed by MAO for olefin polymerization, indicate that the cationic complex has cis-located active sites (A methyl group and a coordinated ethylene are in a cis configuration). These results together with X-ray analysis suggest that complex 1 has a high potential for olefin polymerization. PI Catalysts displayed high ethylene polymerization activities using MAO as a cocatalyst. The activity increased dramatically by introducing a bulky X substituent. One of the complexes (complex 3: possessing a cyclooctyl group at the X position) exhibited a very high activity (33200 kg-PE.mol-Ti-l'h-~) with a very high molecular weight value (My: 317.0 • 104). This activity value, 33200 kg-PE'mol-Ti-~'h-~, is higher than that of Cp2TiCI: under idintical conditions. Ethylene / norbornene copolymerizations were carried out with complex 1 or 2 using MAO as a cocatalyst. Complexes 1 and 2 displayed high activities (complex 1:0.58 kgPolymer.mol-Ti-~.h-~, complex 2:2.73 kg-Polymer.mol-Ti-~'h-~) and produced amorphous polymers. Microstructural analyses using ~3C-NMR spectroscopy suggest that the polymers are ethylene / norbornene copolymers produced via addition polymerization, with norbornene contents of 48.6 mol% (complex 1) and 44.5 mol% (complex 2). GPC analyses revealed that the copolymers have extremely narrow molecular weight distributions (MJMn < 1.25), which suggest that complexes 1 and 2 may have the characteristics of a living ethylene / norbornene copolymerization. Mn increased (>800000) proportionally with the polymerization time (20 min) while the narrow MJMn was retained for each case, which indicates that the copolymerization is living. In conclusion, the catalytic behavior of Ti complexes with two pyrrolide-imine chelate ligands, PI Catalysts, has been introduced. The results summarized herein indicate that titanium complexes possessing two pyrrolide-imine chelate ligands, PI Catalysts, have great potential as high performance new olefin polymerization catalysts. References [1] G. J. P. Biritovsek, V. C. Gibson, D. F. Wass, Angew. Chem., int. Ed. Engl., 38, (1999) 428. [2] S. D. Ittel, L. K Johnson, M. Brookhart, Chem. Rev., 100, (2000) 1169. [3] S. Matsui, M. Mitani, J. Saito, Y. Tohi, H. Makio, N. Matsukawa, Y. Takagi, K. TstmJ, M. Nitabaru, T. Nakano, H. Tanaka, N. Kashiwa, and T. Fujita, J. Am. Chem. Soc., 123, (2001) 6847. [4] M. Mitani, 1~ Furuyama, J. Mohri, J. Saito, S. Ishii, H. Terao, N. Kashiwa, and T. Fujita, J. Am. Chem. Soc., 124, (2002) 7888. [5] H. Makio, N. Kashiwa, and T. Fujita, Adv. Synth. Catal., 344, (2002) 1. Y. Inoue, T. Nakano, H. Tanaka, N. Kashiwa, and T. Fujita, Chem. Lett., 2001, 1060. [6] T. Matsugi, S. Matsui, S. Kojoh, Y. Takagi, Y. Inoue, T. Nakano, T. Fujita, and N. Kashiwa, Macromolecules, 35, (2002) 4880. [7] Y. Suzuki, N. Kashiwa, and T. Fujita, Chem. Lett., 2002, 358. [8] Y. Yoshida, S. Matsui, Y. Takagi, M. Mitani, M. Nitabaru, T. Nakano, H. Tanaka, and T. Fujita, Organometallics, 20, (2001) 4793. [9] Y. Yoshida, J. Saito, M. Mitani, Y. Takagi, S. Matsui, S. Ishii, Y. Nakano, N. Kashiwa, and T. Fujita, Chem. Commun., 2002, 1298.