通过H•从过渡金属化物转移直接产生氧稳定基
Jonathan L Kuo1, John Hartung, Arthur Han
1Department of Chemistry, Columbia University , 3000 Broadway, New York, New York 10027, United States.
Journal of the American Chemical Society
|January 9, 2015
概括
过渡金属化物通过H•转移到醇乙烯有效地产生α-氧基. 这些基因使二聚选择性5-exo循环化成为可能,提供了直接通往被替代的四基的途径.
科学领域:
- 有机化学 有机化学
- 有机金属化学 有机金属化学
- 激进化学 激进化学是什么
背景情况:
- 已知过渡金属化物参与原子转移反应.
- 乙醇乙烯是有机合成中的多功能基质.
- α-基基的生成和反应性对合成应用有兴趣.
研究的目的:
- 为了研究H•从过渡金属化物 (CpCr(CO) 3H) 转移到乙烯 (n-丁乙烯乙烯).
- 为了研究产生的α-基基的后续化学反应.
- 探索这些基因在合成替代四二的有用性.
主要方法:
- 动力测量以确定H•转移的速率常数.
- 检查反应途径和产生的基的产品.
- 对循环化过程的二选择性进行分析.
主要成果:
- 测量了H•从CpCr(CO) 3H转移到n-乙烯乙烯的速率常数.
- 通过这种方法生成的α-Alkoxy基因经历了5-exo循环.
- 与类似的全碳基相比,循环化表现出更高的二聚体选择性.
结论:
- 过渡金属化物介导的H•转移是产生α-氧基的有效方法.
- 这些基提供了一个易于和 diastereoselective 路径,以替代四基.
- 这种方法为合成复杂的循环以太提供了有价值的工具.
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