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金属作为八面体复合体与三脚四联体的奇拉性来源
María Carmona1, Ricardo Rodríguez1, Vincenzo Passarelli1,2
1Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza , Pedro Cerbuna 12, 50009 Zaragoza, Spain.
Journal of the American Chemical Society
|January 6, 2018
概括
具有三脚连接体的奇拉金属复合体实现了可控的绝对配置. 这些纯复合物以高选择性催化迪尔斯-阿尔德反应.
科学领域:
- 有机金属化学
- 不对称的催化
- 协调化学
背景情况:
- 在合成化学中,控制合金属复合物的绝对配置是一个重大挑战.
- 三脚四牙联体为实现金属中心周围的立体化学控制提供了有前途的支架.
研究的目的:
- 开发一种方法,以有效地控制合金属复合物的绝对配置.
- 通过三脚四牙联体合成纯净复合物.
- 在迪尔斯-阿尔德反应中研究这些复合物的酶选择性催化活性.
主要方法:
- 使用 (S) -α-phenylglycine 的赛米复合物的光学分辨率.
- 合成具有一般配方[Rh(κ4C,N,N',P-L) A(Solv]][SbF6]n 的纯复合物.
- 在甲烯和环二烯 (HCp) 之间进行酶选择性迪尔斯-阿尔德反应催化.
- 使用核磁共振 (NMR) 光谱和密度功能理论 (DFT) 研究进行了表征.
主要成果:
- 使用三脚四牙联体L,可以有效地控制合金属复合物的绝对配置.
- 光学分辨率产生了能够催化迪尔斯-阿尔德反应的纯复合物.
- 在甲克罗莱因和HCp之间的Diels-Alder反应中获得高达99/1的反体比.
- NMR和DFT研究阐明了活性物种,酶选择性的起源和机制细节.
结论:
- 三脚四牙连接体L有效控制合金属复合物的绝对配置.
- 合成的纯复合物是迪尔斯-阿尔德反应的高效选择性催化剂.
- 获得了对催化过程和酶选择性的详细机制见解.
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