Ligand-Directed Regioselectivity in Amine–Imine Nickel-Catalyzed 1-Hexene Polymerization
Citations Over TimeTop 10% of 2014 papers
Abstract
1-Hexene polymerizations were carried out with amine–imine nickel complexes [(ArN═C(R1)–(R2R3)CNHAr)NiBr2, 1a, R1 = R2 = R3 = Me, Ar = 2,6-(iPr)2C6H3; 1b, R1 = R2 = R3 = Me, Ar = 2,6-(Me)2C6H3; 2a, R1 = Me, R2 = R3 = H, Ar = 2,6-(iPr)2C6H3; 3a, R1 = Me, R2 = tBu, R3 = H, Ar = 2,6-(iPr)2C6H3] in the presence of MMAO or Et2AlCl. The ligand-directed regioselectivity involving insertion fashion and chain walking in amine–imine nickel-catalyzed 1-hexene polymerization is clearly observed. Catalyst 1a with two methyl substituents on the bridging carbon can polymerize 1-hexene to afford semicrystalline “polyethylene” with long methylene sequence (−(CH2)n–, n = 40–74) via a combination of 90% selectivity of 2,1-insertion fashion and precise chain walking, whereas catalyst 3a with a tert-butyl on the bridging carbon can polymerize 1-hexene in 80% selectivity of 1,2-insertion to produce amorphous polyolefin with predominant methyl branches through 2,6-enchainment.
Related Papers
- → Liquid Phase Hydrogenation of 1-Hexene and 2-Hexene with 30 Å Platinum Particles on Alumina Support.(1980)22 cited
- → IR study of 1-hexene isomerization on HZSM-5 zeolites(1989)8 cited
- → Competitive electron impact induced methylene imine elimination from methyl‐ and dimethylamino N‐heterocycles. 1—substituted melamines(1983)6 cited
- A Study of Double Bond Isomerization of 1-Hexene Catalyzed by Water-soluble Ru-H Complex(2007)