Iridium-Catalyzed Transfer Hydrogenation of 1,10-Phenanthrolines using Formic Acid as the Hydrogen Source
作者:Conghui Xu、Lingjuan Zhang、Chaonan Dong、Jianbin Xu、Yixiao Pan、Yali Li、Hanyu Zhang、Huanrong Li、Zhiyong Yu、Lijin Xu
DOI:10.1002/adsc.201500909
日期:2016.2.18
The iridium‐catalyzed highly regioselective transfer hydrogenation of a variety of 2‐substituted and 2,9‐disubstituted 1,10‐phenanthrolines under mild conditions with formic acid as the hydrogen source is described. In the presence of a catalytic amount of the iridium complex [Cp*IrCl2]2, the transfer hydrogenation proceeded smoothly in 1,4‐dioxane under ligand‐free conditions, exclusively leading
描述了在温和条件下,以甲酸为氢源,铱催化的高度2取代和2,9-二取代的1,10-菲咯啉的高区域选择性转移氢化反应。在催化量的铱络合物[Cp * IrCl 2 ] 2的存在下,转移加氢在1,4-二恶烷中在无配体的条件下平稳进行,仅导致1,2,3,4-高产率的四氢-1,10-菲咯啉产品。由[Cp * IrCl 2 ] 2和(R,R)-(CF 3)2 C 6 H 3 SO原位生成的催化剂2 dpen [ N-(2-氨基-1,2-二苯乙基)-3,5-双(三氟甲基)苯磺酰胺]可以有效地催化这些1,10-菲咯啉在异丙醇(i- PrOH)中的不对称转移氢化可以以高达99%ee的高收率获得手性1,2,3,4-四氢-1,10-菲咯啉。还原成功的关键是溶剂和氢源的选择。