Patent ID: 8859696

Claim:
A process for producing an oligomeric product by oligomerisation of at least one olefinic compound, the process including: a) providing an activated oligomerisation catalyst by combining, in any order, i) a source of chromium; ii) a ligating compound of the formula I (R 1 ) m X 1 (Y)X 2 (R 2 ) n I wherein: X 1 and X 2 are independently an atom selected from the group consisting of nitrogen, phosphorus, arsenic, antimony, bismuth, oxygen, sulphur and selenium or said atom oxidized by S, Se, N or O where the valence of X 1 and/or X 2 allows for such oxidation; Y is a linking group between X 1 and X 2 ; m and n are independently 0, 1 or a larger integer; and R 1 and R 2 are independently hydrogen, a hydrocarbyl group, an organoheteryl group or a heterohydrocarbyl group, and R being the same or different when m>1, and R 2 being the same or different when n>1; iii) a catalyst activator or combination of catalyst activators; b) providing a zinc compound; and c) contacting the at least one clef irk compound with a composition containing the activated oligomerisation catalyst and the zinc compound, the zinc compound being present in a sufficient quantity such that the ratio of the molar amount of zinc in the zinc compound to the molar amount of chromium in the source of chromium is from 10 to 1000.