Zirconium complexes incorporated with asymmetrical tridentate pincer type mono- and di-anionic pyrrolyl ligands: mechanism and reactivity as catalytic precursors
Zirconium complexes incorporated with asymmetrical tridentate pincer type mono- and di-anionic pyrrolyl ligands: mechanism and reactivity as catalytic precursors
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DOI：
10.1039/c2dt30417a
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发表时间：
2012-01-01
影响因子：
4
通讯作者：
Hsu, Wei-Che
中科院分区：
文献类型：
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作者：
Hsu, Jia-Wei;Lin, Yu-Chun;Hsu, Wei-Che
研究了Zr(NR2)(4) （1, R = Me; 2, R = Et）与不对称三齿钳形吡咯配体前体[C4H2NH(2-(CH2NHBu)- bu -t)(5-CH2NMe2)]的反应和PhNCS或PhNCO对衍生物的处理，并进行了表征。Zr(NR2)(4) （1, R = Me; 2, R = Et）与[C4H2NH(2-(CH2NHBu)- bu -t)(5-CH2NMe2)]反应生成Zr[C4H2N(2-(CH2NBu)- bu -t)(5-CH2NMe2)](NR2)(2) (3, R = Me; 4, R = Et)，分别消除2等量的二甲胺和二乙胺。有趣的是，当溶剂由Et2O变为CH2Cl2时，通过C-Cl键裂解生成配合物Zr[C4H2N(2-(CH2NBu)- bu -t)(5- ch2nme2)][C4H2N(2-(CH2NHBu)- bu -t)(5- ch2nme2)]Cl(5)。此外，3或4分别与1或2等量的PhNCS或PhNCO反应生成Zr[C4H2N(2-(CH2NBu)- bu -t)(5-CH2NMe2)](NMe2)[PhNC(NMe2)S] (6), Zr[C4H2N(2-(CH2NBu)- bu -t)(5-CH2NMe2)](NEt2)[PhNC(NEt2)O](7)和Zr[C4H2N(2-(CH2NHBu)- bu -t)(5-CH2NMe2)]-[PhNC(NEt2)O] 3(8)。上述配合物均通过H-1和C-13核磁共振光谱进行了表征，其中5、6和8的分子结构通过单晶x射线衍射测定。配合物4,5和7在MAO作为助催化剂的存在下引发乙烯聚合。
The reactions of Zr(NR2)(4) (1, R = Me; 2, R = Et) with an asymmetrical tridentate pincer type pyrrole ligand precursor [C4H2NH(2-(CH2NHBu)-Bu-t)(5-CH2NMe2)] and treatment of the derivatives with either PhNCS or PhNCO have been carried out and characterized. Reacting Zr(NR2)(4) (1, R = Me; 2, R = Et) with [C4H2NH(2-(CH2NHBu)-Bu-t)(5-CH2NMe2)] generates Zr[C4H2N(2-(CH2NBu)-Bu-t)(5-CH2NMe2)](NR2)(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 Et2O to CH2Cl2, the complex Zr[C4H2N(2-(CH2NBu)-Bu-t)(5-CH2NMe2)][C4H2N(2-(CH2NHBu)-Bu-t)(5-CH2NMe2)]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[C4H2N(2-(CH2NBu)-Bu-t)(5-CH2NMe2)](NMe2)[PhNC(NMe2)S] (6), Zr[C4H2N(2-(CH2NBu)-Bu-t)(5-CH2NMe2)](NEt2)[PhNC(NEt2)O] (7) and Zr[C4H2N(2-(CH2NHBu)-Bu-t)(5-CH2NMe2)]-[PhNC(NEt2)O] 3 (8), respectively. All the aforementioned complexes were characterized by H-1 and C-13 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.