salicylic aldehyde ligand; former transition metal; ethylene trimerization; ultra-high molecular weight polyethylene

Wang C, Friedrich S, Younkin TR, et al. Neutral nickel(II)-based catalysts for ethylene polymerization. Organometallics 1998; 17(15): 3149–3151. doi: 10.1021/om980176y Pong FY, Mandal S, Sen A. Steric and electronic effects in ethene/norbornene copolymerization by neutral salicylaldiminato-ligated palladium(II) catalysts. Organometallics 2014; 33(24): 7044–7051. doi: 10.1021/om500470t Yao E, Wang J, Chen Z, et al. Homo- and heteroligated salicylaldiminato titanium complexes with different substituents ortho to the phenoxy oxygens for ethylene and ethylene/1-hexene (co)polymerization. Macromolecules 2014; 47(23): 8164–8170. doi: 10.1021/ma5017677 Matsui S, Tohi Y, Mitani M, et al. New bis(salicylaldiminato) titanium complexes for ethylene polymerization. Chemistry Letters 1999; 28(10): 1065–1066. doi: 10.1246/cl.1999.1065 Damavandi S, Galland GB, Zohuri GH, et al. FI Zr-type catalysts for ethylene polymerization. Journal of Polymer Research 2010; 18(5): 1059–1065. doi: 10.1007/s10965-010-9507-0 Matsugi T, Fujita T. High-performance olefin polymerization catalysts discovered on the basis of a new catalyst design concept. Chemical Society Reviews 2008; 37(6): 1264. doi: 10.1039/b708843b Breuil PAR, Magna L, Olivier-Bourbigou H. Role of homogeneous catalysis in oligomerization of olefins: Focus on selected examples based on group 4 to group 10 transition metal complexes. Catalysis Letters 2014; 145(1): 173–192. doi: 10.1007/s10562-014-1451-x. Suzuki Y, Kinoshita S, Shibahara A, et al. Trimerization of ethylene to 1-hexene with titanium complexes bearing phenoxy−imine ligands with pendant donors combined with MAO. Organometallics 2010; 29(11): 2394–2396. doi: 10.1021/om1003368 Zhang W, Sun WH, Redshaw C. Tailoring iron complexes for ethylene oligomerization and/or polymerization. Dalton Transactions 2013; 42(25): 8988–8997. doi: 10.1039/c2dt32337k Suttil JA, Shaw MF, McGuinness DS, et al. Synthesis of Ti(iv) complexes of donor-functionalised phenoxy-imine tridentates and their evaluation in ethylene oligomerisation and polymerisation. Dalton Transactions 2013; 42(25): 9129. doi: 10.1039/c3dt32465f Sattler A, Labinger JA, Bercaw JE. Highly selective olefin trimerization catalysis by a borane-activated titanium trimethyl complex. Organometallics 2013; 32(23): 6899–6902. doi: 10.1021/om401098m Soshnikov IE, Semikolenova NV, Ma J, et al. Selective ethylene trimerization by titanium complexes bearing phenoxy-imine ligands: NMR and EPR spectroscopic studies of the reaction intermediates. Organometallics 2014; 33(6): 1431–1439. doi: 10.1021/om500017r Pasha FA, Basset JM, Toulhoat H, et al. DFT study on the impact of the methylaluminoxane cocatalyst in ethylene oligomerization using a titanium-based catalyst. Organometallics 2015; 34(2): 426–431. doi: 10.1021/om5008874 Sattler A, VanderVelde DG, Labinger JA, et al. Lewis acid promoted titanium alkylidene formation: Off-cycle intermediates relevant to olefin trimerization catalysis. Journal of the American Chemical Society 2014; 136(30): 10790–10800. doi: 10.1021/ja5055687 Kirillov E, Roisnel T, Razavi A, et al. Chromium(III) complexes of sterically crowded bidentante {ONR} and tridentate {ONNR} naphthoxy-imine ligands: Syntheses, structures, and use in ethylene oligomerization. Organometallics 2009; 28(8): 2401–2409. doi: 10.1021/om801196d Suzuki Y, Kinoshita S, Shibahara A, et al. Transition Metal Complex Compounds, Olefin Oligomerization Catalysts Including the Compounds, and Processes for Producing Olefin Oligomers Using the Catalysts. U.S. Patent 8,258,361, 4 September 2012. Terao H, Iwashita A, Ishii S, et al. Ethylene/norbornene copolymerization behavior of bis(phenoxy−imine)ti complexes combined with MAO. Macromolecules 2009; 42(13): 4359–4361. doi: 10.1021/ma900890b Terao H, Iwashita A, Matsukawa N, et al. Ethylene and ethylene/α-olefin (co)polymerization behavior of bis(phenoxy−imine)Ti catalysts: Significant substituent effects on activity and comonomer incorporation. ACS Catalysis 2011; 1(4): 254–265. doi: 10.1021/cs100148a Terao H, Ishii S, Mitani M, et al. Ethylene/polar monomer copolymerization behavior of bis(phenoxy–imine)Ti complexes: Formation of polar monomer copolymers. Journal of the American Chemical Society 2008; 130(52): 17636–17637. doi: 10.1021/ja8060479 Zhang X, Liu Z, Yi J, et al. Copolymerization of ethylene with acrylonitrile promoted by novel nonmetallocene catalysts with phenoxy‐imine ligands. Journal of Polymer Science Part A: Polymer Chemistry 2012; 50(10): 2068–2074. doi: 10.1002/pola.25981 Huang W, Sun X, Ma H, et al. Ethylene homopolymerization and ethylene/1-hexene copolymerization catalysed by mixed salicylaldiminato cyclopentadienyl zirconium complexes. Inorganica Chimica Acta 2010; 363(9): 2009–2015. doi: 10.1016/j.ica.2009.06.010 Liu K, Yao G, Wu W, et al. New half-sandwich zirconium(IV) complexes containing salicylaldimine ligands: Synthesis, characterizations and catalytic properties. Chemical Research in Chinese Universities 2014; 30(5): 825–830. doi: 10.1007/s40242-014-4054-6 Han S, Yao E, Qin W, et al. Binuclear heteroligated titanium catalyst based on phenoxyimine ligands: Synthesis, characterization, and ethylene (co)polymerization. Macromolecules 2012; 45(10): 4054–4059. doi: 10.1021/ma300384w Aguilar M, Martín S, Vega JF, et al. Processability of a metallocene‐catalyzed linear PE improved by blending with a small amount of UHMWPE. Journal of Polymer Science Part B: Polymer Physics 2005; 43(21): 2963–2971. doi: 10.1002/polb.20581 Makio H, Kashiwa N, Fujita T. FI catalysts: A new family of high performance catalysts for olefin polymerization. Advanced Synthesis & Catalysis 2002, 344(5): 477–493. doi: 10.1002/1615-4169(200207)344:5%3C477::AID-ADSC477%3E3.0.CO;2-6 Matoishi K, Nakai K, Nagai N, et al. Value-added olefin-based materials originating from FI catalysis: Production of vinyl- and Al-terminated PEs, end-functionalized PEs, and PE/polyethylene glycol hybrid materials. Catalysis Today 2011; 164(1): 2–8. doi: 10.1016/j.cattod.2010.11.078 Weiser MS, Wesolek M, Mülhaupt R. The synthesis and X-ray structure of a phenoxyimine catalyst tailored for living olefin polymerisation and the synthesis of ultra-high molecular weight polyethylene and atactic polypropylene. Journal of Organometallic Chemistry 2006; 691(13): 2945–2952. doi: 10.1016/j.jorganchem.2006.03.020 Wang Y, Fan H, Jie S, et al. Synthesis and characterization of titanium(IV) complexes bearing end functionalized biphenyl: Efficient catalysts for synthesizing high molecular weight polyethylene. Inorganic Chemistry Communications 2014; 41: 68–71. doi: 10.1016/j.inoche.2014.01.005 Liu W, Zhang K, Fan H, et al. Living copolymerization of ethylene/1‐octene with fluorinated FI‐Ti catalyst. Journal of Polymer Science Part A: Polymer Chemistry 2012; 51(2): 405–414. doi: 10.1002/pola.26398 Guo S, Fan H, Bu Z, et al. Synthesis of ultrahigh-molecular-weight ethylene-1-hexene copolymers with high hexene content via living polymerization with fluorinated bis(phenoxy-imine) titanium(IV). Macromolecular Rapid Communications 2014; 36(3): 286–291. doi: 10.1002/marc.201400564