N-(Pyridin-2-yl)picolinamide tetranickel clusters: Synthesis, structure and ethylene oligomerization
摘要:
A series of N-(pyridin-2-yl)picolinamide derivatives was synthesized and characterized. Tetranickel complexes were obtained by stoichiometric reaction of NiBr2 and corresponding ligands, and characterized by elemental and spectroscopic analysis. Moreover, the coordination pattern of complex 3a was confirmed by single-crystal X-ray diffraction. In the structure, two ligands linked two nickel atoms to form a unit, and two units were bridged via mu(3)-OMe and mu(2)-Br to form a tetranickel cluster. These Ni(II) complexes were investigated in ethylene oligomerization and found to exhibit remarkable catalytic activities upon activation with MAO. Reaction conditions as well as ligand environment significantly affected the catalytic performance of the nickel complexes: the highest activity could be achieved to be 2.7 x 10(6) g mol(-1) Ni h(-1). (C) 2009 Elsevier Ltd. All rights reserved.
N-(Pyridin-2-yl)picolinamide tetranickel clusters: Synthesis, structure and ethylene oligomerization
摘要:
A series of N-(pyridin-2-yl)picolinamide derivatives was synthesized and characterized. Tetranickel complexes were obtained by stoichiometric reaction of NiBr2 and corresponding ligands, and characterized by elemental and spectroscopic analysis. Moreover, the coordination pattern of complex 3a was confirmed by single-crystal X-ray diffraction. In the structure, two ligands linked two nickel atoms to form a unit, and two units were bridged via mu(3)-OMe and mu(2)-Br to form a tetranickel cluster. These Ni(II) complexes were investigated in ethylene oligomerization and found to exhibit remarkable catalytic activities upon activation with MAO. Reaction conditions as well as ligand environment significantly affected the catalytic performance of the nickel complexes: the highest activity could be achieved to be 2.7 x 10(6) g mol(-1) Ni h(-1). (C) 2009 Elsevier Ltd. All rights reserved.