This report describes propylene polymerization reactions with titanium complexes bearing carbamato ligands, Ti(O2CNMe2)Cl-2 (I) and Ti(O2CR2)(4) [R-2=NMe2 (II), NEt2 (III) and [GRAPHICS] (IV)]. Combinations of these complexes and MAO form catalysts for the synthesis of atactic polypropylene, as confirmed by FT-IR, DSC and C-13 NMR analysis. Effects of main reaction parameters on the catalyst activity were studied including the type of complex, solvent, temperature, and the [Al]/[Ti] molar ratio. The highest activity was observed when chlorobenzene was used as a solvent and AlMe3-depleted MAO was employed as a cocatalyst. (c) 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 4095-4102