系统的参数确定旨在以催化剂控制的不对称的Rh ((I) 催化剂的休息 - 坎德反应
Yifan Qi1, Luke T Jesikiewicz1, Grace E Scofield1
1Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States.
研究人员确定了在不对称的Pauson-Khand反应 (PKR) 中预测产量和酶选择性的关键因素. 连接物参数,溶剂性质和固体效应显著影响循环化合物中奇拉四元中心的形成.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 不对称的合成方法
背景情况:
- 过渡金属催化使复杂的循环化合物合成成为可能.
- 非对称的帕森-坎德反应 (PKR) 是有价值的,但在基质范围和选择性方面面临挑战.
- 了解影响PKR的因素对于优化性合成至关重要.
研究的目的:
- 在催化剂控制的不对称PKR中确定产量和酶选择性的预测参数.
- 探索连接物特性,溶剂和基质结构对反应结果的影响.
- 为了使环融合式环烯与奇拉四等碳中心的合成.
主要方法:
- 在Rh(I) 催化PKR中利用了1,6-因与2,2-异位的基.
- 相关的双素连接体参数 (例如,Pd单对轨道能量,P-aryl角度) 具有enantioselectivity.
- 研究了溶剂特性 (双极时刻,键基本性) 和对反应结果的固体效应 (斯特里摩尔B1值).
主要成果:
- 建立了连接物参数和酶选择性之间的强烈相关性 (R2 = 0.99,0.91).
- 根据前体极性 (R2 = 0.94,0.93) 证明溶剂对酶选择性的作用.
- 显示 counterions 和 alkyne 替代物的固体需求 (R2 = 0.99) 的显著影响.
- 发现计算的CC波数与不对称的PKR收益率直接相关.
结论:
- 已经确定了控制不对称PKR产量和酶选择性的关键参数.
- 连接体电子,溶剂极性和固态因素对于控制性四元中心形成至关重要.
- 这项研究为优化复杂分子合成的不对称PKR提供了一个预测框架.
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