Synthesis and Characterization of Methyltrioxorhenium(VII) Immobilized in Bipyridyl-Functionalized Mesoporous Silica
作者:Carla D. Nunes、Martyn Pillinger、Anabela A. Valente、Isabel S. Gonçalves、João Rocha、Paula Ferreira、Fritz E. Kühn
DOI:10.1002/1099-0682(200205)2002:5<1100::aid-ejic1100>3.0.co;2-b
日期:2002.5
Methyltrioxorhenium(VII) (MTO) has been immobilized in the mesoporous silica MCM-41 functionalized with pendant bipyridyl (bpy) groups of the type 4-[(−O)3Si(CH2)4]-4′-CH3-2,2′-bipyridine. Powder X-ray diffraction and N2 adsorption-desorption studies confirm that the regular hexagonal symmetry of the host is retained during the grafting reaction and that the channels remain accessible. Solid-state
甲基三氧铼 (VII) (MTO) 已被固定在介孔二氧化硅 MCM-41 中,该介孔二氧化硅 MCM-41 被 4-[(-O)3Si(CH2)4]-4'-CH3-2,2 型双吡啶 (bpy) 侧基官能化'-联吡啶。粉末 X 射线衍射和 N2 吸附-解吸研究证实,在接枝反应过程中保持了主体的规则六边形对称性,并且通道仍然可以进入。固态魔角旋转 NMR 光谱 (29Si, 13C) 也用于监测偶联反应。红外、拉曼和 X 射线吸收精细结构 (XAFS) 光谱证实了 CH3ReO3·bpy 型系链路易斯碱加合物的形成。然而,XAFS 结果确实表明并非所有铼离子都以这种形式存在,这与元素分析一致,其中 Re/N 比为 1:1.1 (0.55 mmol Re g-1)。多余的铼原子很可能作为组装在 MCM 通道中的未配位的 MTO 分子存在。还制备并表征了模型配合物(4-烷基4'-甲基-2,2'-联吡