用皮纳科尔波兰催化氧化胺的降解. 范围和机制
Christopher J Barger1, Rachel D Dicken1, Victoria L Weidner1
1Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States.
Journal of the American Chemical Society
|April 7, 2020
概括
(LaNTMS) 有效地利用皮纳科尔波兰催化胺脱氧降解. 这种选择性反应产生了氨基,并耐受各种功能组,突出显示了胺催化剂的多功能性.
科学领域:
- 有机金属化学
- 催化剂
- 有机合成
背景情况:
- 在有机转化中,均质催化提供了高的选择性和效率.
- 兰化物复合物越来越多地因其在各种反应中的催化潜力而被认可.
- 胺降解是有机合成中的关键转化,使得有价值的氨基产品可以获得.
研究的目的:
- 调查Tris[N,N-bis(trimethylsilyl) amide]lanthanum (LaNTMS) 的催化活性,以减少胺的氧化作用.
- 探索LaNTMS催化还原的反应机制,动力学和范围.
- 证明开发的催化系统的选择性和功能组耐受性.
主要方法:
- 使用LaNTMS作为催化剂的同质催化.
- 用皮纳科尔博兰 (HBpin) 降氧三级和二级胺.
- 动力学研究,同位素标记和密度功能理论 (DFT) 计算.
主要成果:
- 在温和的温度 (25-60°C) 下,NTMS有效地选择性地将胺降解为氨基.
- 该反应对化物,化物和氨基功能组具有很好的耐受性.
- 动力学研究显示出异常的混合顺序速率定律,表明催化剂和HBpin.
- DFT计算提出了一个活跃的催化剂物种,并表明了以基为中心的化物转移.
结论:
- NTMS 是一种多功能且有效的胺脱氧降解催化剂.
- 开发的方法提供了具有广泛功能组兼容性的氨基的选择性途径.
- 这项工作扩展了兰他化物复合物的已知催化应用.
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