Ruthenium-Catalyzed Aromatization of Aromatic Enynes via the 1,2-Migration of Halo and Aryl Groups: A New Process Involving Electrocyclization and Skeletal Rearrangement
作者:Hung-Chin Shen、Sitaram Pal、Jian-Jou Lian、Rai-Shung Liu
DOI:10.1021/ja0379159
日期:2003.12.1
The halo and aryl substituents of the 1,2-disubstituted styryl group of aromatic enynes undergo a 1,2-shift in the aromatization reaction catalyzed by TpRuPPh3(CH3CN)2PF6 (10 mol %) in toluene (110 degrees C, 6-8 h). The aryl group shifts to the neighboring olefin carbon, and the iodo (or bromo) substituent migrates to the terminal alkyne carbon. The mechanisms of these two migrations have been elucidated
芳族烯炔的 1,2-二取代苯乙烯基的卤素和芳基取代基在由 TpRuPPh3(CH3CN)2PF6 (10 mol %) 催化的芳构化反应中发生 1,2-位移(110 摄氏度,6-8 度) H)。芳基转移到相邻的烯烃碳,碘(或溴)取代基转移到末端炔碳。同位素标记实验阐明了这两种迁移的机制。这表明 1,2-芳基位移来自钌-亚乙烯基物种的 5-endo-dig 电环化,而 1,2-iodo 位移遵循 6-endo-dig 途径。