在olefin转化中将活动与可访问性整合起来:一个前所未有的反应性鲁-印尼利丁催化剂
Daniel L Nascimento1, Anna Gawin2, Rafał Gawin2
1Center for Catalysis Research and Innovation, and Department of Chemistry and Biomolecular Sciences , University of Ottawa , Ottawa , Ontario K1N 6N5 , Canada.
Journal of the American Chemical Society
|June 29, 2019
概括
一个新的二元性内尼利丁复合物 (Ru-1) 提供了高度活跃的烯转化催化剂的可扩展合成. 这一突破使高反应性与实际生产相结合,克服了以前的印尼利丁催化剂的局限性.
科学领域:
- 有机金属化学
- 催化剂
- 有机合成
背景情况:
- 由于从不稳定的前体中合成非可扩展的化连接物,对主要的化转化催化剂 (Grubbs,Hoveyda,Grela) 的使用是有限的.
- 尽管安装是可靠的,但乙烯连接物产生反应较低的催化剂.
- 之前的印尼利丁催化剂的启动速度较慢,这归因于循环添加步骤,而不是连接体可变性.
研究的目的:
- 开发一个快速启动的二元性内基复合物,使高催化活性与可扩展的合成相协调.
- 调查连接物可变性对印第利丁催化剂启动速率的作用.
- 评估新催化剂在宏循环和乙醇溶解反应中的性能.
主要方法:
- 合成含有循环氨基碳酸 (CAAC) 和桥接合物的二元性内尼利丁复合物 (Ru-1).
- 通过将Ru-1与已确定的内尼利丁催化剂 (M2,UC) 进行比较来确定启动速率常数.
- 使用乙烯 (C2H4) 进行甲基酸盐的宏环化和乙醇化性能评估.
主要成果:
- 由于不稳定的桥梁联体,二元性内尼利丁复合体Ru-1的启动速度显著快 (比M2快250倍,比UC快65倍).
- 在宏循环和乙醇溶解中,Ru-1 的活性与最先进的CAAC-化基催化剂相当或优于它们.
- 在标准等级乙烯的乙烯溶解中,Ru-1的强度提高了5倍,这可能是由于固体保护.
结论:
- 印尼利丁催化剂的缓慢启动主要是由于配体可变性低,而不是固有的循环添加率.
- 开发的二元性内尼利丁复合物 (Ru-1) 提供了可扩展的高活性和强大的氨酸转化催化剂的途径.
- 鲁-1代表着一个重要的进步,弥合了高性能和实际合成的差距.
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