化物和捐赠者-接受者循环烯酸的Sn (II) 和Sn (IV) 催化循环添加物和捐赠者-接受者循环烯酸
Patrick D Pohlhaus1, Jeffrey S Johnson
1Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, USA.
Journal of the American Chemical Society
|November 17, 2005
概括
一种新的循环加法方法利用化物和循环烯合成了以丰富的四水. 这一策略有效地传输立体化学信息,产生有价值的性异环化合物.
科学领域:
- 有机化学 有机化学
- 合成化学 合成化学
- 异环化学 异环化学
背景情况:
- 四氨基是药物化学中重要的异环基架.
- 替代四水的酶选择性合成仍然是一个挑战.
研究的目的:
- 开发一种新的循环添加策略,用于合成高丰富的2,5-cis-非替代四水 furan.
- 探索在不对称合成中供体-接受体环烯的实用性.
主要方法:
- 正式的 [3 + 2] 循环添加反应由锡(II) 三叶酸 (Sn(OTf) 2) 或锡(IV) 化物 (SnCl4) 催化.
- 作为基质,利用性供体-接受体环和各种化物.
- 机理学研究包括立体化学分析.
主要成果:
- 成功合成了一系列具有光学活性的2,5-cis-异位化四水,具有高反体丰富度.
- 从循环前体转移到四二产品,证明了立体化学信息的有效转移.
- 确定了一种不寻常的SN2反应途径,涉及化物对激活的环烯的核性攻击.
结论:
- 开发的循环添加策略提供了一条有效的途径,以获得对抗聚合物丰富的四氨酸.
- 反应机制突出显示了供体-接受体环烯的新型反应模式.
- 这种方法为构建复杂的性异环分子提供了有价值的工具.
![The Synthesis of [Sn10(Si(SiMe3)3)4]2- Using a Metastable Sn(I) Halide Solution Synthesized via a Co-condensation Technique](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F54498.jpg&w=3840&q=50)
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