兰化物复合物的动态连接体交换导致结构和功能转换:一个电位的序列催化不对称的环氧化-区域选择性环氧化-开放过程
Shin-ya Tosaki1, Riichiro Tsuji, Takashi Ohshima
1Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Journal of the American Chemical Society
|February 17, 2005
概括
这项研究引入了用于催化不对称环氧化和随后环氧化开放的复合物. 序列过程有效地产生具有高选择性和产量的有价值的阿齐多-胺产品.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 兰化物化学 兰化物化学
背景情况:
- 兰化物复合物提供动态连接物交换能力,用于in situ功能改变.
- 不对称的环氧化和随后的转化在合成化学中至关重要.
研究的目的:
- 开发一种用于不对称环氧化和区域选择性环氧化开放的序列催化工艺.
- 研究动态连接体交换在生成反应性中间体中的作用.
主要方法:
- 使用Sm-(S) -BINOL-Ph3As=O复合物的α,β不和胺基的催化不对称环氧化.
- 在现场通过动态连接体交换生成一个samarium azide复合体.
- 使用三甲基酸 (Me3SiN3) 开启环氧化物.
主要成果:
- 对抗β-酸-α-氧胺产品的总产量优异 (高达99%) 和对抗β-酸-α-酸的过量 (高达99%).
- 在环氧化物开放阶段完成区域选择性.
- 通过红外光谱仪在现场生成化复合物的证据.
结论:
- 兰化物复合物的动态连接体交换使得有效的序列催化过程成为可能.
- 亚酸复合物是环氧化物开放的高度反应性中间体.
- 胺部分的易斯基本性在环氧化和开放反应中增强了反应性.
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