形诱导的远程甲基-C-H激活氨基的氨基
Ri-Yuan Tang1, Gang Li1, Jin-Quan Yu1
1Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.
Nature
|March 14, 2014
概括
研究人员开发了一种可回收的模板,用于选择性碳- (C-H) 功能化,使得远距离的甲基-C-H键在11个位置之外的反应成为可能. 这一突破克服了针对C-H激活的挑战,特别是对于几何难以接近的债券.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 合成方法论 合成方法论
背景情况:
- 碳- (C-H) 功能化的位点选择性是由于类似的C-H键反应性而面临的重大挑战.
- 定向的C-H激活通常集中在靠近功能组的位置上,远距离的C-H键很难被准.
- 循环金属化策略在准几何难以接近的C-H键时,经常面临由于环应变的限制.
研究的目的:
- 开发一种新的策略,用于远端元C-H键的定向功能化.
- 克服现有方法在实现远程C-H债券的地点选择性的局限性.
- 为了证明可回收模板在指导具有挑战性的C-H激活反应中的实用性.
主要方法:
- 设计和合成可回收模板,用于指导C-H功能化.
- 模板的应用,以化和乙化远端的甲基-C-H键在anilines和胺胺.
- 使用X射线结晶学和核磁共振 (NMR) 研究来研究该机制,包括形成应变化中间体.
主要成果:
- 可回收模板成功指导了距离C-H键的olefination和acetoxylation,达到11个位置的距离.
- 该方法证明了双循环异循环的超选择性C-H功能化,通过一个紧张的,三循环环类的化中间体.
- 模板中的替代,结合连体选择,允许在正确选择性和元选择性之间切换,突出表达性控制.
结论:
- 一个新的和可回收的模板使以前无法访问的远端元C-H键的位置选择功能化成为可能.
- 开发的方法扩大了针对性C-H激活的范围,提供了新的合成可能性.
- 了解形态偏差和连接体效应为C-H功能化反应中微调选择性提供了一条途径.
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