通过吸引力非共价相互作用控制的催化酶选择性C-H化
Hao Wang1, Yoonsu Park2,3, Ziqian Bai1
1State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry , Nankai University , Tianjin 300071 , China.
Journal of the American Chemical Society
|April 13, 2019
概括
新的性催化剂可实现对选择性C ((sp3) -H功能化. 这项研究引入了通过Csp3-H化合成光学丰富的γ-乳酸盐的催化反应,利用有吸引力的非对应相互作用进行控制.
科学领域:
- 有机化学
- 催化剂
- 不对称的合成
背景情况:
- 对于合成性分子而言,酶选择性C ((sp3) -H功能化至关重要.
- 开发利用非共价相互作用的新型性催化剂对于不对称金属催化是非常可取的.
- 现有的方法通常依赖于固态排斥,限制了更广泛的应用.
研究的目的:
- 开发新型的性催化剂,用于对选择性C ((sp3) -H的功能化.
- 建立一个新的 (III) 催化分子内C (sp3) -H化反应.
- 通过具有吸引力的非对应性相互作用来合成光学丰富的γ-乳酸以加速速度和对抗控制.
主要方法:
- 设计和合成一种基于α-氨基酸的新型连体,用于 (III) 催化.
- 对二氧化基质的分子内C ((sp3) -H化反应的发生.
- 研究反应条件,包括使用水作为辅溶剂.
- 机制研究以阐明反控制机制.
主要成果:
- 通过Ir (III) -催化C (sp3) -H化实现了高抗选择性γ-乳酸盐的合成.
- 在温和的条件下,对已激活和未激活的基C ((sp3) -H键均表现出卓越的效率和反选择性.
- 建立了第一个不对称的γ-alkyl γ-lactams合成的通用途径.
- 作为辅溶剂的水显著提高了对γ- 酸乳合成的反选择性.
- 机理学研究揭示了一个独特的对抗控制机制,该机制是基于在奇拉囊中具有吸引力的非共价相互作用.
结论:
- 新设计的以α-氨基酸为基础的性配体和Ir (III) 催化剂可实现高度反选择性的分子内C (sp3) -H化.
- 这种方法为光学丰富的γ-乳酸提供了通用和有效的途径,包括γ-基和γ-基变体.
- 催化剂通过一种前所未有的机制运作,利用有吸引力的非共价相互作用,扩大了不对称金属催化剂的范围.
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