CATALYTIC PROCESS FOR THE OLIGOMERIZATION OF OLEFINIC MONOMERS

A process for the simultaneous trimerization and tetramerization of olefinic monomers , wherein the process comprises contacting at least one olefinic monomer with catalyst system comprising : a) a source of chromium, molybdenum or tungsten; b) a ligand having the general formula (I) ; (R1)2P-X-P (R1)m(R2)n wherein : X is a bridging group of the formula -N(R3)-, wherein R3 is selected from hydrogen, a hydrocarbyl group, a substituted hydrocarbyl group, a heterohydrocarbyl group, a substituted heterohydrocarbyl group, a silyl group or derivative thereof; the R1 groups are independently selected from an optionally substituted aromatic group bearing a polar substituent on at least one of the ortho-positions; and the R2 groups are independently selected from hydrocarbyl, substituted hydrocarbyl, heterohydrocarbyl and substituted heterohydrocarbyl groups and c) a cocatalyst, at a pressure in the range of from below atmospheric to about 40 barg and at a temperature in the range of from about 0 °C to about 120 °C. The present invention further relates to a process for the simultaneous trimerization and tetramerization of ethylene to 1-hexene and 1 -octene.