Polymerization reactions of ethylene, propylene, higher 1-alkenes (1-hexene, 1-octene, 1-decene, vinyl cyclohexane, 3-methyl-1-butene), and copolymerization reactions of ethylene with 1-octene with a post-metallocene catalyst containing an oxyquinolinyl complex of Ti and a combination of Al(C2H5)(2)Cl and Mg(C4H9)(2) as a cocatalyst were studied. The catalyst is highly active and, judging by the broad molecular weight distribution of the polymers, contains several active center populations. The active centers differ not only in their kinetic parameters but also in stereospecificity. Most of the active centers produce essentially atactic polypropylene but a small fraction of the centers produces polypropylene of moderate isotacticity degree. (c) 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 1844-1854