trihydroquinolylcobalt dichloride: synthesis and polyethylene wax formation

 

a series of 2-(1-(arylimino)ethyl)-8-arylimino-5,6,7-trihydroquinolylcobalt dichloride (aryl = 2,6-r¹-4-r²c₆h₂) pre-catalysts were synthesized and structurally characterized by ft-ir and elemental analyses. the molecular structures of co1 (r¹ = me, r2 = h), co2 (r¹ = et, r² = h) and co5 (r¹ = et, r² = me) were determined by single-crystal x-ray diffraction analysis, and confirmed co1 as a distorted trigonal bipyramidal geometry at the metal, whilst in co2 and co5 the metal is square-pyramidal. upon treatment with either mao or mmao, all cobalt pre-catalysts exhibited highest activities at 60 °c for ethylene polymerization. the resultant polyethylenes, under optimization reaction parameters, possessed low molecular weight (waxes) and narrow polydispersity.