一种易斯酸控制的化的反分异性氧化
Aliakbar Mohammadlou1, Chetan Joshi2, Brendyn P Smith1
1Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States.
ACS catalysis
|March 22, 2024
概括
两种新型催化剂具有VANOL配合或的配合物,可以有效地执行aldehydes的不对称环氧化. 这些催化剂产生高产品量和选择性,每个催化剂产生不同的.
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:
- 催化不对称的环氧化对于合成性分子至关重要.
- 基于VANOL的配体在不对称催化中表现有前途.
- 了解催化剂行为和酶选择性是开发新合成方法的关键.
研究的目的:
- 为了比较两种基于VANOL的环氧化催化剂的有效性:一种是基于的,一种是基于的.
- 为了评估它们在使用diazoacetamides的化物的不对称环氧化中的性能.
- 通过计算方法来研究选择性的机制和起源.
主要方法:
- 合成和应用两个不同的VANOL-合金金属催化剂 (Al和B).
- 催化不对称的环氧化反应与各种芳香性和性化物和酸乙胺.
- 密度函数理论 (DFT) 计算来分析反应机制,速率决定步骤和酶选择性.
主要成果:
- 和VANOL催化剂都显示出高产率和优秀的非对称诱导 (高达99% ee) 在化物环氧化中.
- 催化剂在0°C有效,而催化剂需要较低的温度 (-40°C).
- 重要的是,从 (R) -VANOL衍生出的催化剂产生了相反的环氧体反体,表明了不同的立体化学结果.
结论:
- 与和的VANOL-联结体复合物是非常有效的不对称环氧化催化剂.
- 金属的选择 (Al与B) 影响了最佳反应温度,并决定了环氧化物产品的反体结果.
- DFT计算为观察到的反分歧的机制基础提供了洞察力.
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