Cheng Cungui, Liu Shuiyou, Zhu Gangguo
Department of Chemistry, Zhejiang Normal University, 688 Yingbin Road, Jinhua 321004, China.
Org Lett. 2015 Mar 20;17(6):1581-4. doi: 10.1021/acs.orglett.5b00464. Epub 2015 Mar 12.
A Pd-catalyzed divergent cyclization, including cycloisomerization and aerobic oxidative cycloisomerization of homoallenyl amides, is described. Varieties of functionalized 2-amino-5-alkylfurans and 2-amino-5-formylfurans can be selectively synthesized in good to excellent yields. Preliminary mechanistic studies show that peroxide may be a key intermediate for this Pd-catalyzed radical aerobic oxidative cycloisomerization of homoallenyl amides. The mild reaction conditions, high atom economy, and utilization of air as the oxygen source make this protocol very environmentally benign and practical to the synthetic community.
本文描述了一种钯催化的发散环化反应，包括高烯丙基酰胺的环异构化和需氧氧化环异构化。多种官能化的2-氨基-5-烷基呋喃和2-氨基-5-甲酰基呋喃能够以良好至优异的产率选择性地合成。初步机理研究表明，过氧化物可能是该钯催化的高烯丙基酰胺自由基需氧氧化环异构化反应的关键中间体。温和的反应条件、高原子经济性以及以空气作为氧源，使得该方法对合成领域而言具有良好的环境友好性和实用性。
