基于高活性的选择性乙烯三/四化催化剂,由基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基
Tao Zhou1, Jing Zuo1, Haojie Xie1
1Key Laboratory for Advanced Materials and Institute of Fine Chemicals, School of Chemistry & Molecular Engineering, East China University of Science and Technology, 130 Mei Long Road, Shanghai 200237, China. zhangj@ecust.edu.cn.
Dalton transactions (Cambridge, England : 2003)
|August 6, 2024
概括
新型二非诺胺 (PNP) 连接物使催化选择性乙烯三聚化和四聚化成为可能. 优化的配体实现高活性和选择性,用于有价值的1-hexene和1-octene生产.
科学领域:
- 有机金属化学 有机金属化学
- 催化剂是一种催化剂.
- 聚合物科学 聚合物科学
背景情况:
- 乙烯寡合化对于生产线性α-olefins至关重要.
- 催化剂被广泛使用,但往往缺乏选择性.
- 新型配体的开发是控制催化结果的关键.
研究的目的:
- 合成具有P-基基组的新型二酸胺 (PNP) 配体.
- 研究它们在催化乙烯三/四聚化中的应用.
- 优化连接体结构和反应条件,以提高活性和选择性.
主要方法:
- 一系列新型二氨酸胺 (PNP) 配体的合成.
- 作为催化剂前体的 (III) 乙烯基酸盐 (Cr (acac)) 和改性甲基 (MMAO-3A) 的 in situ 组合.
- 在不同的联体替代和条件下 (如压力,温度) 的乙烯氧化反应.
主要成果:
- 开发了高活性PNP配体,用于选择性乙烯三/四化.
- 一种不对称的二二二基酸联体产生了最高的活性 (2036 kg (g Cr h-1) -1),对1-hexene和1-octene具有81.1 wt%的选择性.
- 一种不对称的混合异烯/乙烯二联体在1256公斤 (g Cr h-1) 时显示出高的1 - 八烯选择性 (65.5%重量%) 和总1 - 六烯/1 - 八烯选择性 (91.5%重量%) (g Cr h-1) 活动.
结论:
- 配体替代和反应条件显著影响催化性能.
- 新型PNP配体为选择性生产有价值的α-olefins提供了一个有前途的途径.
- 这些发现有助于开发有效的催化剂,用于olefin的寡合化.
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