环氧化物开放布是由水促进的
Ivan Vilotijevic1, Timothy F Jamison
1Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
概括
水促进选择性环氧化物开放,用于合成复杂的海洋天然产品. 这种水性介质效应是理解生物系统中的酶选择性的关键.
科学领域:
- 有机化学 有机化学
- 生物化学 生物化学
- 海洋天然产品 海洋天然产品
背景情况:
- 传统的有机化学选择性规则来自于非水性环境.
- 酶在水性介质中起作用,但这种介质对化学选择性的影响尚未完全理解.
- 梯子聚乙烯海洋天然产品的生物合成是一个立体化学难题,因为在有机溶剂中,拟议的环氧化物开放途径在动态上受到不利影响.
研究的目的:
- 研究水性介质在梯子聚乙烯海洋天然产品的立体选择性合成中的作用.
- 解决关于拟议的生物合成途径的动力可行性的20年前的难题.
- 为这些天然产品的核心结构建立一个高收益的合成路径.
主要方法:
- 使用中性水作为反应介质来促进选择性.
- 采用模板四胺基 (THP) 组来指导环氧化物开环反应.
- 研究水中环氧化物级联反应的动力优势.
主要成果:
- 中性水在环氧化物链中起到理想的环开放选择性的最佳促进作用.
- 一个单个模板THP组足以启动一个选择性级联.
- 为梯子聚乙烯核心开发了一种高收益的合成策略.
结论:
- 水性介质的影响对于在有机合成中实现特定的选择性至关重要,反映了酶过程.
- 这些发现为复杂的海洋自然产品提供了可行的合成途径.
- 这项研究强调了水作为生物催化剂和有机合成中的反应介质的重要性.
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Epoxides result from alkene oxidation, which can be achieved by a) air, b) peroxy acids, c) hypochlorous acids, and d) halohydrin cyclization.
Epoxidation with Peroxy Acids
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