在酸化中,一种二的假定中间体
Robin J Hamilton1, Carolyn G Leong, Glen Bigam
1Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2.
Journal of the American Chemical Society
|March 24, 2005
概括
合成和研究了二复合物,特别是转化-[Ru((R) -BINAP) ((H) (((eta2-H2) (((R,R) -dpen) ]+的复合物. 该中间体需要基或化物源来产生催化作用,没有显著的溶剂质子.
科学领域:
- 有机金属化学 有机金属化学
- 催化剂研究研究
- 协调化学 协调化学
背景情况:
- 与像 (R) -BINAP这样的性素连接体的鲁复合体在不对称催化过程中至关重要.
- 了解二联体在阴阳中间体中的行为,是催化剂设计的关键.
研究的目的:
- 合成和表征一种复合物的假定阴离子二中间体.
- 为了研究这种二中间体的稳定性和反应性,与溶剂和催化活性有关.
主要方法:
- 在低温下在H2下与 (R,R) -dpen发生fac-[Ru((R) -BINAP) ((H) ((2-PrOH) 3) +的反应.
- 1H NMR光谱学研究二联体及其相互作用.
- 分析中间体和脱溶剂之间的H-D交换.
主要成果:
- 在没有H-D交换的情况下产生了二中间体trans-[Ru((R) -BINAP) ((H) (((eta2-H2) (((R,R) -dpen) ]+ .
- 二联体并没有显著地对2-PrOH溶剂产生质子.
- 单独的中间体并没有催化活性.
结论:
- 在研究条件下,合成的二中间体是稳定的.
- 这种复合物的催化活性需要添加一个基或化物源.
- 这一发现为化催化剂的激活机制提供了洞察力.
相关概念视频
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