External-Ligand-Free, Nickel-Catalyzed Alkenylation of N-Sulfonylamines with Internal Alkynes
作者:Jia-Yue Li、Lun Li、Hang Shi、Yun-Zhi Lin
DOI:10.1055/s-0040-1719913
日期:2022.8
atom economy, and it uses bench-stable Ni(II)Br2(dme) instead of Ni(0)(COD)2 as the source of the nickel catalyst. Mechanistic studies revealed that a catalytic amount of a strong base (i.e., KO t Bu) was essential for the formation of active Ni(0) catalyst, which, along with an imine intermediate, then initiated the catalytic cycle.
烯丙胺是通过各种N-磺胺和内部炔烃之间的镍催化偶联反应合成的。催化反应无副产物,无需额外的氧化剂/还原剂或活化试剂即可进行。作为对已建立方法的改进,本方法避免了对外部配体的需要,这增加了该方法在原子经济性方面的价值,并且它使用台式稳定的 Ni(II)Br 2 (dme) 代替 Ni(0 )(COD) 2作为镍催化剂的来源。机理研究表明,催化量的强碱(即 KO t Bu) 对活性 Ni(0) 催化剂的形成至关重要,该催化剂与亚胺中间体一起启动了催化循环。