单独的Csp(3) -Csp(3) 与Csp(2) -Csp(3) 从Pt(IV减少消除受制约
Eric G Bowes1, Shrinwantu Pal1, Jennifer A Love1
1Department of Chemistry, The University of British Columbia , Vancouver, British Columbia V6T 1Z1, Canada.
Journal of the American Chemical Society
|December 18, 2015
概括
从刚性 (IV) 复合物中观察到选择性减少的乙. 这种前所未有的反应性是由于连体刚性提高了竞争反应的能量障碍,使得Csp(3) -Csp(3) 键形成.
科学领域:
- 有机金属化学
- 催化剂
- 反应机制
背景情况:
- (IV) 复合物是催化循环中的多功能中间体.
- 减少消除 (RE) 是许多催化转化中的关键步骤.
- 控制减少性消除的选择性对于高效的合成至关重要.
研究的目的:
- 研究从PtIV复合体中选择性减少乙 (Csp3) -Csp3) RE的消除机制.
- 了解连接体支架刚度对Csp(3) -Csp(3) RE和Csp(2) -Csp(3) RE之间的竞争的影响.
- 为了实现前所未有的反应性,
主要方法:
- 具有不同灵活性的 (IV) 复合物的合成和表征.
- 涉及化物抽象和热解的实验研究.
- 计算理论研究 (例如,DFT) 来分析反应路径和能量障碍.
主要成果:
- 从刚性Pt (IV) 复合体中观察到选择性的Csp (III) -Csp (III) RE.
- 证明了连接体支架的刚性增加了Csp(2) -Csp(3) RE的障碍.
- 鉴定出由于连接体刚性的影响而出现的前所未有的反应性.
结论:
- 连接体设计,特别是支架刚性,是控制Pt(IV) 减少性消除的强大工具.
- 刚性配体可以抑制不必要的Csp(2) -Csp(3) RE通路,有利于Csp(3) -Csp(3) RE.
- 这项工作为开发涉及Pt(IV) 中间体的选择性催化过程开辟了新的途径.
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