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In this study, bis(diphenylphosphinemethyl)dimethyl silane (L1) and its palladium(II) halide complex, L1/PdCl2 (C1), were synthesized and characterized. Single‐crystal X‐ray analysis of the complex revealed bidentate coordination at the Pd center. In combination with methylaluminoxane (MAO) as co‐catalyst, C1 exhibited excellent catalytic activity and selectivity for ethylene dimerization toward butene. The maximum catalytic activity obtained from the C1/MAO system for ethylene dimerization to yield butenes was 7.33 × 105 g/(molPd·h). The selectivity toward butene remained stable and high (> 96%) over the various conditions.

A series of ligands and cobalt complexes were synthesized and characterized using NMR spectroscopy, elemental analysis and single-crystal X-ray diffrac-features a monomeric structure with κ 2 coordination of the silicon-bridged diphosphine ligand to the cobalt center.Using dried methylaluminoxane (DMAO) and AlEt 3 as co-catalysts and methylcyclohexane as solvent, the Co(II) complex proved to be moderately active and highly selective for ethylene dimerization. The effects of ligand structure, catalyst loading, reaction temperature, Al/Co molar ratio, DMAO/ AlEt 3 molar ratio and reaction time were investigated with respect to the catalytic activity and product selectivity of ethylene dimerization. Cobalt complex C1 exhibited moderate catalytic activity of 2.3 × 10 5 g (mol Co ) −1 h −1 , with 100% selectivity towards C 4 (87% 1-C 4 in the C 4 fraction).