A Sustainable Heterogeneous Iron Catalyst Fe/SBA-15 towards Direct Arylation of Unactivated C(sp<sup>3</sup>
)−H and C(sp<sup>2</sup>
)−H Bonds with Arenes
作者:C. Rajendran、G. Satishkumar
DOI:10.1002/cctc.201601562
日期:2017.4.7
Iron grafted over mesoporous silica (8 wt %Fe/SBA‐15) is a sustainable, efficient heterogeneous iron catalyst for direct arylation of biphenyl methane C(sp3)−H and benzene C(sp2)−H bonds. The selective extraction deposition (SED) technique was adopted to graft iron easily over the mesoporous support SBA‐15 by using LaFeO3 as an iron precursor. The synthesized catalyst has been characterized by EPR
介孔二氧化硅(8 wt%Fe / SBA-15)上接枝的铁是一种可持续,高效的非均质铁催化剂,用于联苯甲烷C(sp 3)-H和苯C(sp 2)-H键的直接芳构化。采用选择性萃取沉积(SED)技术通过使用LaFeO 3轻松将铁接枝在介孔载体SBA-15上作为铁的前体。合成的催化剂已通过EPR光谱,漫反射紫外/可见光谱和程序升温还原(TPR)分析进行了表征,从而了解了介孔SBA-15上接枝的氧化铁物种的配位环境和状态。TPR结果证实了催化剂中存在分离的,簇状的,低聚的氧化铁物质。采用的SED技术在将8 wt%的铁接枝到SBA-15的中孔而不形成氧化铁颗粒方面非常成功。与均质铁不同,8 wt%Fe / SBA-15催化剂不需要吸电子基团的支持和添加剂即可进行苯的芳基化反应,并且可以成功回收五次。