基的减少阿扎-帕森-坎德反应
Hong-Gui Huang1, Yu-Qing Zheng1, Dayou Zhong1
1Sauvage Center for Molecular Sciences, Engineering Research Center of Organosilicon Compounds & Materials (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China.
Journal of the American Chemical Society
|May 2, 2023
概括
这项研究引入了一种用于合成双循环γ- lactams的新型还原性aza- Pauson- Khand反应 (aza- PKR). 该方法有效地创建复杂的乳结构,并允许使用水进行合.
科学领域:
- 有机合成
- 医学化学
- 催化剂
背景情况:
- 在药物和有机合成中,γ-乳酸是关键的结构基因.
- 现有的γ-乳糖合成方法往往缺乏效率或立体化学控制.
- 帕森-坎德反应及其aza变体是构建循环系统的强大工具.
研究的目的:
- 开发一种用于双环α,β-不和γ-乳酸盐的新合成途径.
- 探索尼特利作为降解性aza-Pauson-Khand反应 (aza-PKR) 的基质的实用性.
- 研究反应的机械路径和立体化学结果.
主要方法:
- 一种由催化的还原性aza-Pauson-Khand反应 ([2+2+1]循环添加) 涉及,和八乙烯 (Co2(CO) 8).
- 作为起始材料使用基结合的malononitriles.
- 使用实验技术和密度函数理论 (DFT) 计算的初步机制研究.
- 使用D2O进行合研究
主要成果:
- 具有两个相邻立体中心的多种双循环α,β-不和γ-乳酸盐的有效合成.
- 进入含有高二元选择性的全碳四元中心的结构.
- 机械洞察力揭示了 aza-PKR 随后的 in situ 减少.
- 使用D2O在g-位置进行现场生成的降解剂的演示.
结论:
- 这项工作建立了直接利用烯的新型降解性aza-PKR γ-lactam合成.
- 开发的方法为复杂的γ-lactam支架提供了实用和二重选择性途径.
- 这种反应为进一步的合成加工和标签研究提供了多功能平台.
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