A novel transition metal based pro-catalyst and a process for its preparation

A catalyst composition comprising:

• i. a transition metal based pro-catalyst represented by Formula I;
• wherein,
• R1, R2, R4, R6 R8, R10 and R12 are same or different, and independently selected from the group consisting of hydrogen, aryl, hetero-aryl and halide;
• R5 and R9 are tertiary alkyl groups;
• R7 and R11 are same or different, and independently selected from the group consisting of hydrogen and tertiary alkyl group;
• R3 is independently selected from the group consisting of hydrogen, halogen, alkoxy, aryloxy, carboxylic and sulphonic;
• M is a transition metal selected from the group consisting of Hafnium (Hf), Manganese (Mn), Iron (Fe), Rhenium (Re), Tungsten (W), Niobium (Nb), Tantalum (Ta), Vanadium (V) and Titanium (Ti);
• X is a halide selected from the group consisting of Cl, Br and I;
• and
• n is an integer 2,
• ii. at least one alkyl aluminium co-catalyst;
• and
• iii. at least one inert hydrocarbon liquid medium.