摘要
Abstract
Novel pyridine diimine iron complexes were synthesized by introducing alkyl groups with varying steric hindrance on the carbon atoms of pyridine monoimines,specifically 2-propyl-6-ethylpyridine diimine iron(Cat-1)and 2,6-dipropylpyridine diimine iron.The structures of these complexes were characterized by NMR,XRD,and GC.Their catalytic activities were evaluated through ethylene oligomerization reactions.The experimental results indicate that both complexes exhibit high catalytic activity for ethylene oligomerization,with Cat-1 demonstrating the highest activity,significantly surpassing that of previously reported classical catalysts.When modified methylalumoxane is employed as a co-catalyst and the amount of Cat-1 is relatively low,the catalytic ethylene oligomerization activity can reach up to 92.2×107 g/(mol·h).An increase in ethylene pressure enhances the catalytic activity of Cat-1,whereas a decrease in pressure facilitates the reduction of waxy components in the product.As ethylene pressure increases,the n(C14)∶n(C15)of the product gradually rises,and the proportion of high-carbon-number olefins progressively increases.关键词
吡啶二亚胺/吡啶二亚胺铁络合物/铁系催化剂/乙烯齐聚Key words
pyridine diimine/pyridine diimine iron complex/iron-based catalyst/ethylene oligomerization分类
化学化工
