chromium(II) complex, Cr2[(NtBuSiMe2)2O]2 (2). Similar reaction of CrCl3 with 1 yielded the corresponding chromium(III) complex, Cr2[(NtBuSiMe2)2O]3 (3). The dinuclear structure of 3 was revealed by X-ray crystallography, in which the disiloxanediamido ligand can be regarded as an N,N-bidentate ligand. The complexes 2 and 3 showed relatively high catalytic activities for ethylenepolymerization upon activation
CrCl 2与0.5当量的Li 4 [(N t BuSiMe 2)2 O] 2(1)反应生成新的铬(II)络合物Cr 2 [(N t BuSiMe 2)2 O] 2(2)。CrCl 3与1的相似反应产生相应的铬(III)络合物Cr 2 [(N t BuSiMe 2)2 O] 3(3)。3的双核结构X射线晶体学表明,其中二硅氧烷二酰胺基配体可被认为是N,N-双齿配体。配合物2和3在用二乙基氯化铝活化后对乙烯聚合显示出较高的催化活性。