通过介导的 [2 + 2 + 2] 循环添加合成宏循环
Llorente V R Boñaga1, Han-Cheng Zhang, Alessandro F Moretto
1Drug Discovery, Johnson & Johnson Pharmaceutical, Research & Development, Spring House, Pennsylvania 19477-0776, USA.
Journal of the American Chemical Society
|March 10, 2005
概括
这项研究详细介绍了从α,o-diynes. cobalt-catalyzed宏循环的形成. 改进的条件使得能够有效合成含比里丁的宏循环,为有机化学家提供了灵活的方法.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 宏分子科学 宏分子科学
背景情况:
- 宏循环化合物在各种科学领域都至关重要.
- 复杂宏观循环的高效合成仍然是一个挑战.
- 以为媒介的循环三聚化为新型宏观循环结构提供了一条途径.
研究的目的:
- 通过使用介导的共循环三聚化,研究从α,omega-diynes中形成宏循环.
- 开发改进的反应条件,用于合成含有皮里丁的宏循环.
- 探索这些循环加法反应的区域选择性和范围.
主要方法:
- 催化 [2+2+2] 循环添加的α,omega-diynes与烯,胺或异酸盐.
- 作为催化剂使用了CpCo(CO) 2 (Cp = 环丁)
- 优化反应参数,包括温度,溶剂和反应时间.
主要成果:
- 成功合成了含有甲的宏循环,包括甲和甲.
- 受到左边长度和立体电子因素影响的区域选择性.
- 实现了高产量和改进的反应条件,例如,在100°C时为diyne 6与p-tolunitrile的87%的产量.
- 通过使用异酸盐,展示了使用宏环型氨酸的高效合成,例如,44p的64%收益率.
- 报告了Vollhardt反应的宏循环变体,与基因共循环化二烯酸.
结论:
- 开发了一种方便和灵活的合成协议,用于宏环皮里丁化合物.
- 改进的介导的 [2+2+2] 循环添加是宏观循环合成的强大工具.
- 区域选择性可以通过基质设计和反应条件来控制.
相关概念视频
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01:16[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction
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Direct addition products are formed faster owing to...
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Direct addition products are formed faster owing to...
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01:22Consecutive Reactions
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