A highly selective ethylene tetramerization catalyst

Small change, big difference: The introduction of an additional CH2 group into the bridge of ligands with two P/N units leads to a different selectivity of the corresponding chromium-based catalysts. Whereas 1 produces an ethylene trimerization system, 2 provides an unprecedented ethylene tetramerization system that produces 1-octene with high purity and little or no polymer side products (see scheme; DMAO=Me3Al-depleted methylaluminoxane)