A kind of (ArO)TiR3 (AK) = 2,6-(R')(2)-4-methylphenolate, R' = Me, Bu-t, CH2SPh, CH2N(Pr-i)(2), CH2NPh2) complexes was synthesized and characterized. X-ray analysis of 6a and 7 shows that neither -CH2SPh (6a) nor CH2N(Pr-i)(2) group (7) coordinates to titanium. Large bond angles C(Ar)-O(1)-Ti(1) angel (152.9(2)degrees in 6a and 175.33 degrees in 7 indicate that the bond have partial sp-hybridized character. Upon treatment with modified methylaluminoxane (MMAO), the titanium complexes exhibit significant thermal stability, and prove useful as styrene syndiotactic polymerization catalysts. Comparisons between different complexes on the styrene polymerization were discussed. Steric instead of electronic properties at 2,6-positions of phenol affect the polymerization activity. (2-tert-Butyl)-4-methylphenoxytitanium(IV) chloride 5e was established the most efficient one. High activity (1.11 x 10(5) g sPS/mol(Ti) h) was achieved when styrene polymerization was carried out in the presence of 5e/MMAO at 130 degrees C for 2 h. (C) 2013 Elsevier B.V. All rights reserved.