Titanium-based precatalysts, bearing C-3 or pseudo-C-s symmetric aminotriol ligands, upon activation with methylaluminoxane, polymerize hex-1-ene to give polymers of high molecular weight, i.e., 50000 and 600000, respectively, with low dispersity, 1.2-1.4, and high isotacticity, 85-60%, depending on the overall symmetry of the precatalysts, but when one arm of the aminotriol ligands is methylated to yield C-2 or meso aminodiol ligands, their corresponding titanium catalysts gave higher-molecular-weight polyhexenes, 300000 to 250000, with lower dispersities, 1.07-1.11, which possibly suggests living polymerization, with activities 200-500 times greater than that of the parent C-3 and pseudo-C-s catalysts.