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Novel polymerization catalysts and hydride clusters from rare-earth metal dialkyls

Abstract

This Review gives an overview on recent progress in the synthesis and chemistry of rare-earth metal dialkyl complexes bearing monoanionic ancillary ligands, with an emphasis on novel polymerization catalysts. These structurally well-defined and highly reactive compounds are prepared either by alkane elimination reactions between trialkyl rare-earth complexes and acidic neutral ligands, or by the metathetical reactions of rare-earth trihalides with the alkali metal salts of the corresponding ligands. On treatment with an appropriate borate compound, the dialkyl complexes are converted into the corresponding cationic monoalkyl species, which serve as excellent catalysts for the polymerization and copolymerization of a variety of olefins to yield a series of new polymer materials that exhibit novel properties. Alternatively, hydrogenation of the dialkyl rare-earth complexes with H2 affords a new class of rare-earth polyhydride complexes with unique features in terms of both their structure and reactivity.

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Figure 1: A general scheme showing the synthesis and important transformations of rare-earth dialkyls.
Figure 2: Synthesis of half-sandwich rare-earth dialkyl complexes.
Figure 3: Representative examples of rare-earth metal dialkyl complexes bearing monoanionic, non-Cp ligands.
Figure 4: Synthesis of cationic rare-earth alkyl complexes from dialkyl precursors.
Figure 5: Regio- and stereospecific polymerization of styrene and isoprene catalysed by cationic rare-earth alkyl complexes.
Figure 6: Half-sandwich Sc-catalysed copolymerization of various olefins.
Figure 7: Synthesis and reactions of polynuclear rare-earth polyhydride complexes bearing the C5Me4SiMe3 (Cp') ligand.
Figure 8: Synthesis of polynuclear rare-earth polyhydride complexes bearing mono-anionic, non-Cp ligands.

References

  1. Marques, N., Sella, A. & Takats, J. Chemistry of the lanthanides using pyrazolylborate ligands. Chem. Rev. 102, 2137–2159 (2002).

    Article  CAS  PubMed  Google Scholar 

  2. Molander, G. A. & Romero, J. A. C. Lanthanocene catalysts in selective organic synthesis. Chem. Rev. 102, 2161–2185 (2002).

    Article  CAS  PubMed  Google Scholar 

  3. Hou, Z. & Wakatsuki, Y. Recent developments in organolanthanide polymerization catalysts. Coord. Chem. Rev. 231, 1–22 (2002).

    Article  CAS  Google Scholar 

  4. Piers, W. E. & Emsile, D. J. H. Non-cyclopentadienyl ancillaries in organo group 3 metal chemistry: a fine balance in ligand design. Coord. Chem. Rev. 233, 131–155 (2002).

    Article  Google Scholar 

  5. Gromada, J., Carpentier, J. F. & Mortreux, A. Group 3 metal catalysts for ethylene and α-olefin polymerization. Coord. Chem. Rev. 248, 397–410 (2004).

    Article  CAS  Google Scholar 

  6. Schumann, H., Meese-Marktscheffel, J. A. & Esser, L. Synthesis, structure, and reactivity of organometallic π-complexes of the rare earths in the oxidation state Ln3+ with aromatic ligands. Chem. Rev. 95, 865–986 (1995).

    Article  CAS  Google Scholar 

  7. Evans, W. J. Organometallic lanthanide chemistry. Adv. Organomet. Chem. 24, 131–177 (1985).

    Article  CAS  Google Scholar 

  8. Edelmann, F. T. in Comprehensive Organometallic Chemistry III Ch. 4.01 (eds Crabtree, R. H. & Mingos, M. P.) 1−190 (Elsevier, 2007).

    Book  Google Scholar 

  9. Hou, Z. & Wakatsuki, Y. in Science of Synthesis Vol. 2 (eds Imamoto, T. & Noyori, R.) 849–942 (Thieme, 2002).

    Google Scholar 

  10. Yasuda, H. Organo-rare-earth-metal initiated living polymerizations of polar and nonpolar monomers. J. Organomet. Chem. 647, 128–138 (2002).

    Article  CAS  Google Scholar 

  11. Kirillov, E., Lehmann, C. W., Razavi, A. & Carpentier, J.-F. Highly syndiospecific polymerization of styrene catalyzed by allyl lanthanide complexes. J. Am. Chem. Soc. 126, 12240–12241 (2004).

    Article  CAS  PubMed  Google Scholar 

  12. Rodrigues, A.-S. et al. Allyl ansa-lanthanidocenes: Single-component, single-site catalysts for controlled syndiospecific styrene and styrene–ethylene (co)polymerization. Chem. Eur. J. 13, 5548–5565 (2007).

    Article  CAS  Google Scholar 

  13. Hultzsch, K. C., Voth, P., Beckerle, K., Spaniol, T. P. & Okuda, J. Single-component polymerization catalysts for ethylene and styrene: synthesis, characterization, and reactivity of alkyl and hydrido yttrium complexes containing a linked amido-cyclopentadienyl ligand. Organometallics 19, 228–243 (2000).

    Article  CAS  Google Scholar 

  14. Hou, Z. et al. C5Me5/ER-ligated samarium(II) complexes with the neutral “C5Me5M” ligand (ER ) OAr, SAr, NRR′, or PHAr; M = K or Na): a unique catalytic system for polymerization and block-copolymerization of styrene and ethylene. J. Am. Chem. Soc. 122, 10533–10543 (2000).

    Article  CAS  Google Scholar 

  15. Fu, P.-F. & Marks, T. J. Silanes as chain transfer agents in metallocene-mediated olefin polymerization. Facile in situ catalytic synthesis of silyl-terminated polyolefins. J. Am. Chem. Soc. 117, 10747–10748 (1995).

    Article  CAS  Google Scholar 

  16. Hou, Z. & Wakatsuki, Y. Lanthanide(II) complexes bearing mixed linked and unlinked cyclopentadienyl-monodentate-anionic ligands. J. Organomet. Chem. 647, 61–70 (2002).

    Article  CAS  Google Scholar 

  17. Shapiro, P. J., Cotter, W. D., Schaefer, W. P., Labinger, J. A. & Bercaw, J. E. Model Ziegler-Natta α-olefin polymerization catalysts derived from [{(η5-C5Me4)SiMe2(η1-NCMe3)}(PMe3)Sc(μ2-H)]2 and [((η5-C5Me4)SiMe2(η1-NCMe3))Sc(μ2-CH2CH2CH3)]2. Synthesis, structures, and kinetic and equilibrium investigations of the catalytically active species in solution. J. Am. Chem. Soc. 116, 4623–4640 (1994).

    Article  CAS  Google Scholar 

  18. Evans, W. J., Ulibarri, T. A. & Ziller, J. W. Reactivity of (C5Me5)2Sm and related species with alkenes: synthesis and structural characterization of a series of organosamarium allyl complexes. J. Am. Chem. Soc. 112, 2314–2324 (1990).

    Article  CAS  Google Scholar 

  19. Evans, W. J., Ulibarri, T. A. & Ziller, J. W. Reactivity of (C5Me5)2Sm with aryl-substituted alkenes: synthesis and structure of a bimetallic styrene complex that contains an η2-arene lanthanide interaction. J. Am. Chem. Soc. 112, 219–223 (1990).

    Article  CAS  Google Scholar 

  20. Jeske, G., Schock, L. E., Swepston, P. N., Schumann, H. & Marks, T. J. Highly reactive organolanthanides. Synthesis, chemistry, and structures of 4f hydrocarbyls and hydrides with chelating bis(polymethylcyclopentadieny1) ligands. J. Am. Chem. Soc. 107, 8103–8110 (1985).

    Article  CAS  Google Scholar 

  21. Zeimentz, P. M., Arndt, S., Elvidge, B. R. & Okuda, J. Cationic organometallic complexes of scandium, yttrium, and the lanthanoids. Chem. Rev. 106, 2404–2433 (2006).

    Article  CAS  PubMed  Google Scholar 

  22. Hou, Z., Luo, Y. & Li, X. Cationic rare earth metal alkyls as novel catalysts for olefin polymerization and copolymerization. J. Organomet. Chem. 691, 3114–3121 (2006).

    Article  CAS  Google Scholar 

  23. Hou, Z., Nishiura, M. & Shima, T. Synthesis and reactions of polynuclear polyhydrido rare earth metal complexes containing “(C5Me4SiMe3)LnH2” units: a new frontier of rare earth metal hydride chemistry. Eur. J. Inorg. Chem. 2535–2545 (2007).

  24. Hou, Z. Recent progress in the chemistry of rare earth metal alkyl and hydrido complexes bearing mono(cyclopentadienyl) ligands. Bull. Chem. Soc. Jpn 76, 2253–2266 (2003).

    Article  CAS  Google Scholar 

  25. Hultzsch, K. C., Spaniol, T. P. & Okuda, J. Half-sandwich alkyl and hydrido complexes of yttrium: convenient synthesis and polymerization catalysis of polar monomers. Angew. Chem. Int. Ed. 38, 227–230 (1999).

    Article  CAS  Google Scholar 

  26. Luo, Y., Baldamus, J. & Hou, Z. Scandium half-metallocene-catalyzed syndiospecific styrene polymerization and styrene–ethylene copolymerization: unprecedented incorporation of syndiotactic styrene–styrene sequences in styrene–ethylene copolymers. J. Am. Chem. Soc. 126, 13910–13911 (2004).

    Article  CAS  PubMed  Google Scholar 

  27. Ravasio, A. et al. Copolymerization of ethylene with norbornene catalyzed by cationic rare-earth metal half-sandwich complexes. Macromolecules 41, 9565–9569 (2008).

    Article  CAS  Google Scholar 

  28. Li, X., Nishiura, M., Hu, L., Mori, K. & Hou, Z. Alternating and random copolymerization of isoprene and ethylene catalyzed by cationic half-sandwich scandium alkyls. J. Am. Chem. Soc. 131, 13870–13882 (2009).

    Article  CAS  PubMed  Google Scholar 

  29. Cameron, T. M., Gordon, J. C. & Scott, B. L. Synthesis and characterization of (mono)pentamethylcyclopentadienyl lutetium complexes: formation of bipyridyl-stabilized alkyls, anilides, and terminal acetylides. Organometallics 23, 2995–3002 (2004).

    Article  CAS  Google Scholar 

  30. Xu, X., Chen, Y. & Sun, J. Indenyl abstraction versus alkyl abstraction of [(Indenyl)ScR2(THF)] by [Ph3C][B(C6F5)4]: aspecific and syndiospecific styrene polymerization. Chem. Eur. J. 15, 846–850 (2009).

    Article  CAS  PubMed  Google Scholar 

  31. Wang, B., Cui, D. & Lv, K. Highly 3,4-selective living polymerization of isoprene with rare earth metal fluorenyl N-heterocyclic carbene precursors. Macromolecules 41, 1983–1988 (2008).

    Article  CAS  Google Scholar 

  32. Li, X., Nishiura, M., Mori, K., Mashiko, T. & Hou, Z. Cationic scandium aminobenzyl complexes. Synthesis, structure and unprecedented catalysis of copolymerization of 1-hexene and dicyclopentadiene. Chem. Commun. 4137–4139 (2007).

  33. Yu, N., Nishiura, M., Li, X., Xi, Z. & Hou, Z. Cationic scandium allyl complexes bearing mono(cyclopentadienyl) ligands: synthesis, novel structural variety, and olefin-polymerization catalysis. Chem. Asian J. 3, 1406–1414 (2008).

    Article  CAS  PubMed  Google Scholar 

  34. Taube, R., Maiwald, S. & Sieler, J. Komplexkatalyse LVII. Vereinfachte synthese des Nd(π-C3H5)3·C4H8O2 nach der Grignard-methode und darstellung der neuen allylneodym(III)-komplexe [Nd(π-C5Me5)(π-C3H5)2·C4H8O2] und [Nd(π-C3H5)Cl(THF)5]B(C6H5)4·THF als präkatalysatoren für die stereospezifische butadienpolymerisation. J. Organomet. Chem. 621, 327–336 (2001).

    Article  CAS  Google Scholar 

  35. Tardif, O., Nishiura, M. & Hou, Z. Rare earth alkyl and hydride complexes bearing silylene-linked cyclopentadienyl-phosphido ligands. Synthesis, structures, and catalysis in olefin hydrosilylation and ethylene polymerization. Tetrahedron 59 10525–10539 (2003).

    Article  CAS  Google Scholar 

  36. Zhang, L., Luo, Y. & Hou, Z. Unprecedented isospecific 3,4-polymerization of isoprene by cationic rare earth metal alkyl species resulting from a binuclear precursor. J. Am. Chem. Soc. 127, 14562–14563 (2005).

    Article  CAS  PubMed  Google Scholar 

  37. Zimmermann, M., Törnroos, K. W. & Anwander, R. Cationic rare-earth-metal half-sandwich complexes for the living trans-1,4-isoprene polymerization. Angew. Chem. Int. Ed. 47, 775–778 (2008).

    Article  CAS  Google Scholar 

  38. Robert, D., Spaniol, T. P. & Okuda, J. Neutral and monocationic half-sandwich methyl rare-earth metal complexes: synthesis, structure, and 1,3-butadiene polymerization catalysis. Eur. J. Inorg. Chem. 2801–2809 (2008).

  39. Nishiura, M., Mashiko, T. & Hou, Z. Synthesis and styrene polymerisation catalysis of η5- and η1-pyrrolyl-ligated cationic rare earth metal aminobenzyl complexes. Chem. Commun. 2019–2021 (2008).

  40. Jaroschik, F. et al. Synthesis, characterization, and reactivity of mono(phospholyl)lanthanoid(III) bis(dimethylaminobenzyl) complexes. Organometallics 26, 5654–5660 (2007).

    Article  CAS  Google Scholar 

  41. Fang, X., Li, X., Hou, Z., Assoud, J. & Zhao, R. 1,2-Azaborolyl-ligated half-sandwich complexes of scandium(III) and lutetium(III): synthesis, structures, and syndiotactic polymerization of styrene. Organometallics 28, 517–522 (2009).

    Article  CAS  Google Scholar 

  42. Lee, L., Berg, D. J., Einstein, F. W. & Batchelor, R. J. Synthesis, X-ray crystal structure, and reactivity of Y(MAC)(CH2SiMe3)2 (MAC = deprotonated aza-18-crown-6). Organometallics 16, 1819–1821 (1997).

    Article  CAS  Google Scholar 

  43. Lee, L. W. M., Piers, W. E., Elsegood, M. R. J., Clegg, W. & Parvez, M. Synthesis of dialkylscandium complexes supported by β-diketiminato ligands and activation with tris(pentafluorophenyl)borane. Organometallics 18, 2947–2949 (1999).

    Article  CAS  Google Scholar 

  44. Hayes, P. G. et al. Dialkylscandium complexes supported by β-diketiminato ligands: synthesis, characterization, and thermal stability of a new family of organoscandium complexes. Organometallics 20, 2533–2544 (2001).

    Article  CAS  Google Scholar 

  45. Bambirra, S., van Leusen, D., Meetsma, A., Hessen, B. & Teuben, J. H. Neutral and cationic yttrium alkyl complexes with linked 1,4,7-triazacyclononane-amide monoanionic ancillary ligands: synthesis and catalytic ethene polymerization. Chem. Commun. 637–638 (2001).

  46. Hayes, P. G., Piers, W. E. & McDonald, R. Cationic scandium methyl complexes supported by a β-diketiminato (“nacnac”) ligand framework. J. Am. Chem. Soc. 124, 2132–2133 (2002).

    Article  CAS  PubMed  Google Scholar 

  47. Cameron, T. M., Gordon, J. C., Michalczyk, R. & Scott, B. L. Unusual alkyl group activation and cationic complex formation from a novel lutetium dialkyl complex supported by a tridentate monoanionic ligand. Chem. Commun. 2282–2283 (2003).

  48. Bambirra, S., Bouwkamp, M., Meetsman, A. & Hessen, B. One ligand fits all: cationic mono(amidinate) alkyl catalysts over the full size range of the group 3 and lanthanide metals. J. Am. Chem. Soc. 126, 9182–9183 (2004).

    Article  CAS  PubMed  Google Scholar 

  49. Bambirra, S. et al. Yttrium alkyl and benzyl complexes with amino-amidinate monoanionic ancillary ligands. Organometallics 19, 3197–3204 (2000).

    Article  CAS  Google Scholar 

  50. Sánchez-Barba, L. F., Hughes, D. L., Humphrey, S. M. & Bochmann, M. New bis(allyl)(diketiminato) and tris(allyl) lanthanide complexes and their reactivity in the polymerization of polar monomers. Organometallics 24, 3792–3799 (2005).

    Article  CAS  Google Scholar 

  51. Marinescu, S. C., Agapie, T., Day, M. W. & Bercaw, J. E. Group 3 dialkyl complexes with tetradentate (L, L, N, O; L = N, O, S) monoanionic ligands: synthesis and reactivity. Organometallics 26, 1178–1190 (2007).

    Article  CAS  Google Scholar 

  52. Otero, A. et al. Scandium and yttrium complexes supported by NNCp heteroscorpionate ligands: synthesis, structure, and polymerization of ɛ-caprolactone. Organometallics 27, 976–983 (2008).

    Article  CAS  Google Scholar 

  53. Li, S. et al. New rare earth metal bis(alkyl)s bearing an iminophosphonamido ligand. Synthesis and catalysis toward highly 3,4-selective polymerization of isoprene. Organometallics 27, 718–725 (2008).

    Article  CAS  Google Scholar 

  54. Lyubov, D. M. et al. Selective assembly of trinuclear rare-earth alkyl hydrido clusters supported by amidopyridinate ligands. Organometallics 27, 2905–2907 (2008).

    Article  CAS  Google Scholar 

  55. Zimmermann, M., Törnroos, K. W., Waymouth, R. M. & Anwander, R. Structure-reactivity relationships of amido-pyridine-supported rare-earth-metal alkyl complexes. Organometallics 27, 4310–4317 (2008).

    Article  CAS  Google Scholar 

  56. Wang, D., Li, S., Liu, X., Gao, W. & Cui, D. Thiophene-NPN ligand supported rare-earth metal bis(alkyl) complexes. Synthesis and catalysis toward highly trans-1,4 selective polymerization of butadiene. Organometallics 27, 6531–6538 (2008).

    Article  CAS  Google Scholar 

  57. Kenward, A. L., Piers, W. E. & Parvez, M. Low-coordinate organoyttrium complexes supported by β-diketiminato ligands. Organometallics 28, 3012–3020 (2009).

    Article  CAS  Google Scholar 

  58. Zhang, L., Nishiura, M., Yuki, M., Luo, Y. & Hou, Z. Isoprene polymerization with yttrium amidinate catalyst: switching the regio- and stereoselectivity by addition of AlMe3 . Angew. Chem. Int. Ed. 47, 2642–2645 (2008).

    Article  CAS  Google Scholar 

  59. Zhang, L., Suzuki, T., Luo, Y., Nishiura, M. & Hou, Z. Cationic alkyl rare-earth metal complexes bearing an ancillary bis(phosphinophenyl)amido ligand: a catalytic system for living cis-1,4-polymerization and copolymerization of isoprene and butadiene. Angew. Chem. Int. Ed. 46, 1909–1913 (2007).

    Article  CAS  Google Scholar 

  60. Cheng, J. et al. Scorpionate-supported dialkyl and dihydride lanthanide complexes: ligand- and solvent-dependent cluster hydride formation. Angew. Chem. Int. Ed. 47, 4910–4913 (2008).

    Article  CAS  Google Scholar 

  61. Ohashi, M. et al. Rare-earth metal alkyl and hydride complexes stabilized by a cyclen-derived [NNNN] macrocyclic ancillary ligand. J. Am. Chem. Soc. 130, 6920–6921 (2008).

    Article  CAS  PubMed  Google Scholar 

  62. Schaverien, C. J. Cationic lanthanide alkyl complexes. Evidence for an unprecedented tetraphenylborate coordination mode in La(C5Me5){CH(SiMe3)2}BPh4 . Organometallics 11, 3476–3478 (1992).

    Article  CAS  Google Scholar 

  63. Hajela, S., Schaefer, W. P. & Bercaw, J. E. Highly electron deficient group 3 organometallic complexes based on the 1,4,7-trimethyl-1,4,7-triazacyclononane ligand system. J. Organomet. Chem. 532, 45–53 (1997).

    Article  CAS  Google Scholar 

  64. Arndt, S., Spaniol, T. P. & Okuda, J. Homogeneous ethylene-polymerization catalysts based on alkyl cations of the rare-earth metals: are dicationic mono(alkyl) complexes the active species? Angew. Chem. Int. Ed. 42, 5075–5079 (2003).

    Article  CAS  Google Scholar 

  65. Hayes, P. G., Piers, W. E. & Parves, M. Cationic organoscandium β-diketiminato chemistry: arene exchange kinetics in solvent separated ion pairs. J. Am. Chem. Soc. 125, 5622–5623 (2003).

    Article  CAS  PubMed  Google Scholar 

  66. Lawrence, S. C., Ward, B. D., Dubberley, S. R., Kozak, C. M. & Mountford, P. Highly efficient ethylene polymerisation by scandium alkyls supported by neutral fac-k3 coordinated N3 donor ligands. Chem. Commun. 2880–2881 (2003).

  67. Izod, K., Liddle, S. T. & Clegg, W. Protonation of a lanthanum phosphide-alkyl occurs at the P–La not the C–La bond: isolation of a cationic lanthanum alkyl complex. Chem. Commun. 1748–1749 (2004).

  68. Hayes, P. G., Piers, W. E. & Parves, M. Synthesis, structure, and ion pair dynamics of β-diketiminato-supported organoscandium contact ion pairs. Organometallics 24, 1173–1183 (2005).

    Article  CAS  Google Scholar 

  69. Elvidge, B. R., Arndt, S., Zeimentz, P. M., Spaniol, T. P. & Okuda, J. Cationic rare-earth metal trimethylsilylmethyl complexes supported by THF and 12-crown-4 ligands: synthesis and structural characterization. Inorg. Chem. 44, 6777–6788 (2005).

    Article  CAS  PubMed  Google Scholar 

  70. Ward, B. D., Bellemin-Laponnaz, S. & Gade, L. H. C3 Chirality in polymerization catalysis: a highly active dicationic scandium(III) catalyst for the isoselective polymerization of 1-hexene. Angew. Chem. Int. Ed. 44, 1668–1671 (2005).

    Article  CAS  Google Scholar 

  71. Arndt, S., Beckerle, K., Zeimentz, P. M., Spaniol, T. P. & Okuda, J. Cationic yttrium methyl complexes as functional models for polymerization catalysts of 1,3-dienes. Angew. Chem. Int. Ed. 44, 7473–7477 (2005).

    Article  CAS  Google Scholar 

  72. Tredget, C. S., Bonnet, F., Cowley, A. R. & Mountford, P. The first rare earth organometallic complex of 1,4,7-trithiacyclononane: a precursor to unique cationic ethylene and α-olefin polymerisation catalysts supported by an all-sulfur donor ligand. Chem. Commun. 3301–3303 (2005).

  73. Henderson, L. D., MacInnis, G. D., Piers, W. E. & Parves, M. A new family of monocyclopentadienyl organoscandium bis-alkyls supported by a bulky trialkylphosphine oxide ancillary. Can. J. Chem. 82, 162–165 (2004).

    Article  CAS  Google Scholar 

  74. Luo, Y. & Hou, Z. Polymerization of 1-hexene and copolymerization of ethylene with 1-hexene catalyzed by cationic half-sandwich scandium alkyls. Stud. Surf. Sci. Catal. 161, 95–104 (2006).

    Article  CAS  Google Scholar 

  75. Zhang, H., Luo, Y. & Hou, Z. Scandium-catalyzed syndiospecific copolymerization of styrene with isoprene. Macromolecules 41, 1064–1066 (2008).

    Article  CAS  Google Scholar 

  76. Bonnet, F., Visseaux, M., Pereira, A. & Barbier-Baudry D. Highly trans-stereospecific isoprene polymerization by neodymium borohydrido catalysts. Macromolecules 38, 3162–3169 (2005).

    Article  CAS  Google Scholar 

  77. Luo, Y. & Hou, Z. A five-center rather than a four-center transition state for alkene insertion into the metal-alkyl bond of a cationic binuclear yttrium complex. Organometallics 25, 6162–6165 (2006).

    Article  CAS  Google Scholar 

  78. Ajellal, N., Furlan, L., Thomas, C. M., Casagrande, O. L. Jr & Carpentier, J. F. Mixed aluminum-magnesium-rare earth allyl catalysts for controlled isoprene polymerization: modulation of stereocontrol. Macromol. Rapid Commun. 27, 338–343 (2006).

    Article  CAS  Google Scholar 

  79. Chien, J. C. W. & Nozaki, T. Ethylene-hexene copolymerization by heterogeneous and homogeneous Ziegler-Natta catalysts and the “comonomer” effect. J. Polym. Sci. A 31, 227–237 (1993).

    Article  CAS  Google Scholar 

  80. Irwin, L. J., Reibenspies, J. H. & Miller, S. A. A sterically expanded “constrained geometry catalyst” for highly active olefin polymerization and copolymerization: an unyielding comonomer effect. J. Am. Chem. Soc. 126, 16716–16717 (2004).

    Article  CAS  PubMed  Google Scholar 

  81. Rodrigues, A.-S., Kirillov, E., Vuillemin, B., Razavi, A. & Carpentier, J. F. Stereocontrolled styrene–isoprene copolymerization and styrene-ethylene-isoprene terpolymerization with a single-component allyl ansa-neodymocene catalyst. Polymer 49, 2039–2045 (2008).

    Article  CAS  Google Scholar 

  82. Li, X. & Hou, Z. Organometallic catalysts for copolymerization of cyclic olefins. Coord. Chem. Rev. 252, 1842–1869 (2008).

    Article  CAS  Google Scholar 

  83. Tritto, I., Boggioni, L. & Ferro, D. R. Metallocene catalyzed ethene- and propene co-norbornene polymerization: mechanisms from a detailed microstructural analysis. Coord. Chem. Rev. 250, 212–241 (2006).

    Article  CAS  Google Scholar 

  84. Li, X., Baldamus, J. & Hou, Z. Alternating ethylene-norbornene copolymerization catalyzed by cationic half-sandwich scandium complexes. Angew. Chem. Int. Ed. 44, 962–965 (2005).

    Article  CAS  Google Scholar 

  85. Li, X. & Hou, Z. Scandium-catalyzed copolymerization of ethylene with dicyclopentadiene and terpolymerization of ethylene, dicyclopentadiene, and styrene. Macromolecules 38, 6767–6769 (2005).

    Article  CAS  Google Scholar 

  86. Suzuki, H., Matsumura, S., Satoh, Y., Sogoh, K. & Yasuda, H. Random and block copolymerizations of norbornene with conjugated 1,3-dienes catalyzed by novel Ni compounds involving N- or O-donated ligands. React. Funct. Polym. 59, 253–266 (2004).

    Article  CAS  Google Scholar 

  87. Tardif, O., Nishiura, M. & Hou, Z. Isolation and structural characterization of a polyhydrido lanthanide cluster complex consisting of “(C5Me4SiMe3)LuH2” units. Organometallics 22, 1171–1173 (2003).

    Article  CAS  Google Scholar 

  88. Hultzsch, K. C., Voth, P., Spaniol, T. P. & Okuda, J. Synthesis and characterization of a tetranuclear hydride cluster of yttrium [{(η5-C5Me4SiMe3)Y}4(μ-H)4(μ3-H)4(THF)2]. Z. Anorg. Allg. Chem. 629, 1272–1276 (2003).

    Article  CAS  Google Scholar 

  89. Yousufuddin, M. et al. Neutron diffraction studies on a 4-coordinate hydrogen atom in an yttrium cluster. J. Am. Chem. Soc. 130, 3888–3891 (2008).

    Article  CAS  PubMed  Google Scholar 

  90. Cui, D., Tardif, O. & Hou, Z. Tetranuclear rare earth metal polyhydrido complexes composed of “(C5Me4SiMe3)LnH2” units. Unique reactivities toward unsaturated C–C, C–N, and C–O bonds. J. Am. Chem. Soc. 126, 1312–1313 (2004).

    Article  CAS  PubMed  Google Scholar 

  91. Tardif, O., Hashizume, D. & Hou, Z. Hydrogenation of carbon dioxide and aryl isocyanates by a tetranuclear tetrahydrido yttrium complex. Isolation, structures, and CO2-insertion reactions of methylene diolate and μ3-oxo yttrium complexes. J. Am. Chem. Soc. 126, 8080–8081 (2004).

    Article  CAS  PubMed  Google Scholar 

  92. Cui, D., Nishiura, M. & Hou, Z. Rare earth metal imido complexes and their reactions with benzonitrile. Angew. Chem. Int. Ed. 44, 959–962 (2005).

    Article  CAS  Google Scholar 

  93. Luo, Y., Baldamus, J., Tardif, O. & Hou, Z. DFT study of the tetranuclear lutetium and yttrium polyhydride cluster complexes [(C5Me4SiMe3)4Ln4H8] (Ln = Lu, Y) that contain a four-coordinate hydrogen atom. Organometallics 24, 4362–4366 (2005).

    Article  CAS  Google Scholar 

  94. Shima, T. & Hou, Z. Hydrogenation of carbon monoxide by tetranuclear rare earth metal polyhydrido complexes. Selective formation of ethylene and isolation of well-defined polyoxo rare earth metal clusters. J. Am. Chem. Soc. 128, 8124–8125 (2006).

    Article  CAS  PubMed  Google Scholar 

  95. Li, X., Baldamus, J., Nishiura, M., Tardif, O. & Hou, Z. Cationic rare earth polyhydrido complexes: synthesis, structure, and catalytic activity for the cis-1,4-selective polymerization of 1,3-cyclohexadiene. Angew. Chem. Int. Ed. 45, 8184–8188 (2006).

    Article  CAS  Google Scholar 

  96. Evans, W. J., Meadows, J. H., Hunter, W. E. & Atwood, J. L. Organolanthanide and organoyttrium hydride chemistry. 5. Improved synthesis of [(C5H4R)2YH(THF)]2 complexes and their reactivity with alkenes, alkynes, 1,2-propadiene, nitriles, and pyridine, including structural characterization of an alkylideneamido product. J. Am. Chem. Soc. 106, 1291–1300 (1984).

    Article  CAS  Google Scholar 

  97. Bercaw, J. E., Davies, D. L. & Wolczanski, P. T. Reactions of alkyl and hydride derivatives of permethylscandocene and -zirconocene with nitriles and amines. Catalytic hydrogenation of tert-butyl cyanide with permethylscandocene hydride. Organometallics 5, 443–450 (1986).

    Article  CAS  Google Scholar 

  98. Takenaka, Y., Shima, T., Baldamus, J. & Hou, Z. Reduction of transition metal-coordinated carbon monoxide by a rare earth hydride cluster. Isolation of well-defined heteromultimetallic oxycarbene, oxymethyl, carbene, and methyl complexes. Angew. Chem. Int. Ed. 48, 7888–7891 (2009).

    Article  CAS  Google Scholar 

  99. Cheng, J., Ferguson, M. J. & Takats, J. Synthesis and reaction of [(TpiPr2)LnH2]3 (Ln = Y, Lu) with CO: trinuclear cluster-bound propenolate en route to selective formation of propene. J. Am. Chem. Soc. 132, 2–3 (2010).

    Article  CAS  PubMed  Google Scholar 

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Correspondence to Zhaomin Hou.

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Nishiura, M., Hou, Z. Novel polymerization catalysts and hydride clusters from rare-earth metal dialkyls. Nature Chem 2, 257–268 (2010). https://doi.org/10.1038/nchem.595

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