通过不对称的催化来拦截短暂的循环
Michael M Yamano1, Andrew V Kelleghan1, Qianzhen Shao1
1Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, USA.
Nature
|August 27, 2020
概括
化学家们开发了一种催化不对称的反应,以控制压力循环阿伦中的立体化学反应. 这种方法拦截了赛米中间体,为高反质纯度的复杂分子创造新的途径.
科学领域:
- 有机化学
- 不对称的催化
- 应变化学
背景情况:
- 应力循环有机分子,包括循环基,由于显著的环应力而表现出高反应性.
- 这些中间体在合成中很有价值,但在立体化学上很难控制.
- 控制绝对立体化学的现有方法通常依赖于静态度的性试剂,限制了催化方法.
研究的目的:
- 开发一种催化不对称的反应,以从压缩的循环烯中产生缩产物.
- 研究控制这些变化的绝对立体化学机制.
主要方法:
- 在催化不对称反应中拦截racemic循环亚伦中间体.
- 使用计算研究来阐明反应机制.
- 研究了烯体的动态分化和中间π-基复合物的脱对称.
主要成果:
- 证明了能够控制循环变的绝对立体化学的催化不对称反应.
- 确定了两种不同的机制:阿类反体的动态分化和π-类中间体的脱对称化.
- 计算研究显示了一种触媒循环,涉及初始运动差异化,随后是脱对称化.
结论:
- 这项研究扩展了已知的循环亚伦的反应性,超出了传统的循环添加和核捕获.
- 为开发涉及压力循环中间体的新型催化不对称反应提供基础.
- 提供了对具有挑战性的周期性亚伦反应的立体控制策略的见解.
相关概念视频
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