摘要
The reactions of Zr(NR 2 ) 4 (1, R = Me; 2, R = Et) with an asymmetrical tridentate pincer type pyrrole ligand precursor [C 4 H 2 NH(2-CH 2 NH t Bu)(5-CH 2 NMe 2 )] and treatment of the derivatives with either PhNCS or PhNCO have been carried out and characterized. Reacting Zr(NR 2 ) 4 (1, R = Me; 2, R = Et) with [C 4 H 2 NH(2-CH 2 NH t Bu)(5-CH 2 NMe 2 )] generates Zr[C 4 H 2 N(2-CH 2 N t Bu)(5-CH 2 NMe 2 )](NR 2 ) 2 (3, R = Me; 4, R = Et) in high yield along with the elimination of 2 equiv of dimethylamine or diethylamine, respectively. Interestingly, while changing the solvent from Et 2 O to CH 2 Cl 2 , the complex Zr[C 4 H 2 N(2-CH 2 N t Bu)(5-CH 2 NMe 2 )][C 4 H 2 N(2-CH 2 NH t Bu)(5-CH 2 NMe 2 )]Cl (5) is produced by undergoing C-Cl bond cleavage. Furthermore, reaction of either 3 or 4 with 1 or 2 equiv of PhNCS or PhNCO yields Zr[C 4 H 2 N(2-CH 2 N t Bu)(5-CH 2 NMe 2 )](NMe 2 )[PhNC(NMe 2 )S] (6), Zr[C 4 H 2 N(2-CH 2 N t Bu)(5-CH 2 NMe 2 )](NEt 2 )[PhNC(NEt 2 )O] (7) and Zr[C 4 H 2 N(2-CH 2 NH t Bu)(5-CH 2 NMe 2 )][PhNC(NEt 2 )O] 3 (8), respectively. All the aforementioned complexes were characterized by 1 H and 13 C NMR spectrometry and the molecular structures of 5, 6, and 8 have been determined by single-crystal X-ray diffractometry. Complexes 4, 5, and 7 initiated the ethylene polymerization in the presence of MAO as the co-catalyst. © 2012 The Royal Society of Chemistry.