Ligands and catalyst systems for the oligomerization of olefinic monomers

Abstract

The present invention relates to ligands and catalyst systems and a process for the simultaneous trimerization and tetramerization of olefinic monomers using said ligands, the ligands having the general formula (I):(R)P—P(R)(R)═N(R)  (I)wherein Ris selected from hydrogen, a hydrocarbyl group, a substituted hydrocarbyl group, a heterohydrocarbyl group, a substituted heterohydrocarbyl group, a silyl group or derivative thereof;the Rgroups are independently selected from an optionally substituted aromatic group bearing a polar substituent on at least one of the ortho-positions; andthe Rgroups are independently selected from hydrocarbyl, substituted hydrocarbyl, heterohydrocarbyl and substituted heterohydrocarbyl groups with the proviso that when the group is aromatic it does not contain a polar substituent at any of the ortho-positions;with the proviso that m is 0 or 1, n is 1 or 2 and the total of m+n is 2.