TY - JOUR AB - The mechanism of ethylene trimerization and tetramerization with a chromium-diphosphinoamine (Cr-PNP) catalyst system has been studied by theoretical (DFT) methods. Two representative ligands have been explored, namely Ph2 PN(Me)PPh2 and (o-MeC6 H4 )2 PN(Me)P(o-MeC6 H4 )2 . Calculations on the former ligand reveal how a combination of single and double ethylene insertion mechanisms may lead to 1-hexene, 1-octene and the major side products (cyclopentanes and n-alkanes). For the latter ligand, introduction of o-alkyl substitution leads to a more sterically congested active species, which suppresses the available pathways for tetramerization and side product formation. Hence, the high selectivity of o-aryl substituted PNP ligands for trimerization can be rationalized. AU - Britovsek,GJ AU - McGuinness,DS DO - 10.1002/chem.201603909 EP - 16896 PY - 2016/// SN - 0947-6539 SP - 16891 TI - A DFT mechanistic study on ethylene tri- and tetramerization with Cr/PNP catalysts: single versus double insertion pathways T2 - Chemistry - A European Journal UR - http://dx.doi.org/10.1002/chem.201603909 UR - http://www.ncbi.nlm.nih.gov/pubmed/27723144 UR - http://hdl.handle.net/10044/1/41536 VL - 22 ER -