通过- (III) 复合物催化激活远端基
Unai Prieto-Pascual1, Aitor Martínez de Morentin1, Duane Choquesillo-Lazarte2
1Facultad de Química, Universidad del País Vasco (UPV/EHU), 20018, San Sebastián, Spain. miguelangel.huertos@ehu.es.
Dalton transactions (Cambridge, England : 2003)
|June 20, 2023
概括
新的 (III) 催化剂高效地执行双重异构化-水化,将内部烯酸转化为线性烯酸. 阴阳复合物,特别是固态阻碍的2-L2,在远端基的水化中表现出高活性.
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.
- 合成化学 合成化学
背景情况:
- 双重异构化-水化是一种关键反应,用于从内部烯酸中合成线性烯酸.
- (III) 复合物,特别是不和阴离子复合物,是这种转化过程的有效催化剂.
- 基于的双酸连接体在调整催化剂性能方面发挥着至关重要的作用.
研究的目的:
- 合成和表征新型中性和阴离子Rh (III) 复合物,其中包括基于的双酸连接物.
- 为了评估这些复合物的催化活性,在双重异构化-水化反应.
- 研究结构-活性关系,特别是固体阻碍对催化性能的影响.
主要方法:
- 合成六个Rh (III) 复合物:三种中性 ([RhCl (H) (L) PPh3)) 和三种阴离子 ([Rh (H) (L) (PPh3) 2) [BArF4]),利用体L1,L2和L3.
- 使用X射线衍射来确定其固态结构的选择复合物 (1-L2和2-L2) 的表征.
- 在远程基的水化过程中对催化活性进行评估,比较中性和阴离子复合物的性能.
主要成果:
- 中性Rh(III) 复合物 (1-L1,1-L2,1-L3) 被合成和表征,其中1-L2 呈现出扭曲的三角形双金字塔结构,但它们没有显示出催化活性.
- 合成了阴离子Rh(III) 复合物 (2-L1,2-L2,2-L3),其中2-L2呈现正方形金字塔结构.
- 阴离子复合物2-L1,2-L2和2-L3在远端基的水化中表现出显著的催化活性,其中最受硬质阻碍的复合物2-L2是最活跃的.
结论:
- 含有基于的双酸连接体的阴离子Rh (III) 复合体是远端基的水化有效的催化剂.
- 链体结构中的固体阻碍,如2-L2所示,对催化活性产生积极影响.
- 中性复合物是无效的催化剂,这突显了性质对于这种特定转化的重要性.
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